Most often in September, 26 days.
Highest follower count seen that year: 87,197.
January
Jan 5 17:00–24:00 Jan 6 14:00–20:00 Jan 7 18:00–24:00 Jan 8 00:00–01:00, 18:00–23:00 Jan 9 16:00–24:00 Jan 10 00:00–01:00, 16:00–24:00 Jan 11 00:00–01:00, 16:00–24:00 Jan 12 13:00–18:00 Jan 13 19:00–24:00 Jan 14 00:00–01:00, 17:00–24:00 Jan 15 00:00–02:00, 14:00–19:00, 23:00–24:00 Jan 16 00:00–01:00 Jan 17 18:00–21:00 Jan 22 20:00–24:00 Jan 23 00:00–01:00, 14:00–17:00, 21:00–22:00 Jan 24 15:00–19:00, 22:00–24:00 Jan 25 00:00–01:00, 15:00–24:00 Jan 26 14:00–18:00 Jan 27 18:00–24:00 Jan 28 00:00–02:00, 14:00–17:00, 21:00–24:00 Jan 29 00:00–01:00, 20:00–24:00 Jan 30 14:00–17:00, 22:00–24:00 Jan 31 00:00–02:00, 14:00–17:00, 19:00–24:00
February
Feb 1 00:00–02:00 Feb 4 15:00–24:00 Feb 5 00:00–02:00, 14:00–18:00, 22:00–24:00 Feb 6 18:00–24:00 Feb 7 00:00–01:00, 15:00–17:00, 21:00–24:00 Feb 8 00:00–02:00, 15:00–23:00 Feb 11 18:00–23:00 Feb 12 00:00–02:00, 15:00–17:00, 21:00–23:00 Feb 13 00:00–04:00, 15:00–18:00, 22:00–24:00 Feb 14 00:00–03:00, 15:00–17:00, 21:00–24:00 Feb 15 00:00–03:00, 13:00–16:00, 20:00–24:00 Feb 16 00:00–03:00 Feb 18 15:00–19:00, 23:00–24:00 Feb 19 00:00–01:00, 15:00–17:00, 21:00–24:00 Feb 20 00:00–02:00, 15:00–18:00, 22:00–24:00 Feb 21 00:00–03:00, 15:00–24:00 Feb 22 00:00–01:00, 15:00–18:00, 21:00–24:00 Feb 23 00:00–03:00 Feb 24 16:00–18:00, 20:00–23:00 Feb 25 19:00–24:00 Feb 26 01:00–03:00, 15:00–17:00, 22:00–24:00 Feb 27 00:00–03:00, 13:00–17:00, 23:00–24:00 Feb 28 00:00–02:00, 14:00–21:00
March
Mar 1 16:00–23:00 Mar 4 00:00–02:00, 14:00–20:00 Mar 5 20:00–24:00 Mar 6 00:00–01:00, 15:00–18:00, 22:00–24:00 Mar 7 00:00–01:00, 15:00–16:00, 21:00–24:00 Mar 8 00:00–01:00, 15:00–24:00 Mar 10 16:00–17:00 Mar 11 17:00–24:00 Mar 12 00:00–01:00, 15:00–17:00, 20:00–24:00 Mar 13 01:00–04:00, 15:00–18:00, 22:00–24:00 Mar 14 00:00–02:00, 15:00–17:00, 20:00–24:00 Mar 15 00:00–05:00 Mar 17 23:00–24:00 Mar 18 00:00–01:00, 20:00–24:00 Mar 19 00:00–01:00, 22:00–23:00 Mar 20 15:00–18:00, 21:00–24:00 Mar 21 15:00–17:00, 22:00–24:00 Mar 22 00:00–03:00, 20:00–24:00 Mar 25 19:00–24:00 Mar 26 16:00–17:00, 22:00–24:00 Mar 27 00:00–01:00, 16:00–18:00, 23:00–24:00 Mar 28 00:00–04:00, 15:00–19:00, 22:00–24:00 Mar 29 00:00–01:00, 14:00–16:00 Mar 31 15:00–17:00, 22:00–24:00
April
Apr 1 00:00–02:00 Apr 2 21:00–24:00 Apr 3 00:00–01:00, 16:00–18:00, 22:00–24:00 Apr 4 00:00–03:00, 15:00–18:00, 22:00–24:00 Apr 5 00:00–02:00, 15:00–16:00, 22:00–24:00 Apr 6 00:00–01:00 Apr 8 20:00–24:00 Apr 9 21:00–24:00 Apr 10 00:00–03:00, 15:00–18:00 Apr 11 00:00–02:00, 20:00–24:00 Apr 12 00:00–01:00, 14:00–16:00, 21:00–24:00 Apr 14 19:00–21:00 Apr 15 00:00–04:00, 16:00–18:00, 22:00–24:00 Apr 16 00:00–03:00, 23:00–24:00 Apr 17 00:00–01:00 Apr 22 20:00–24:00 Apr 23 16:00–24:00 Apr 24 16:00–18:00, 23:00–24:00 Apr 25 00:00–03:00, 15:00–18:00, 20:00–23:00 Apr 26 23:00–24:00 Apr 27 00:00–01:00 Apr 28 23:00–24:00 Apr 29 00:00–02:00, 19:00–24:00 Apr 30 00:00–01:00, 14:00–17:00, 22:00–24:00
May
May 1 00:00–03:00 May 2 15:00–17:00, 23:00–24:00 May 3 00:00–02:00, 14:00–16:00, 22:00–23:00 May 7 23:00–24:00 May 8 00:00–02:00, 14:00–16:00 May 10 21:00–24:00 May 11 00:00–02:00 May 13 19:00–22:00 May 14 00:00–03:00, 19:00–24:00 May 15 00:00–02:00, 16:00–17:00, 20:00–24:00 May 16 00:00–02:00 May 17 16:00–23:00 May 18 00:00–03:00 May 19 16:00–17:00 May 20 00:00–03:00, 23:00–24:00 May 21 00:00–02:00, 22:00–24:00 May 22 00:00–03:00, 21:00–24:00 May 23 00:00–02:00, 15:00–17:00, 21:00–24:00 May 24 00:00–02:00, 16:00–19:00, 22:00–24:00 May 25 00:00–02:00 May 26 22:00–24:00 May 27 00:00–02:00, 22:00–24:00 May 28 00:00–02:00, 15:00–17:00 May 29 16:00–18:00, 23:00–24:00 May 30 00:00–02:00, 15:00–17:00, 21:00–22:00 May 31 22:00–24:00
June
Jun 1 00:00–04:00, 17:00–19:00 Jun 5 15:00–17:00, 22:00–24:00 Jun 6 00:00–01:00, 15:00–17:00 Jun 7 15:00–19:00, 22:00–24:00 Jun 8 00:00–02:00 Jun 9 22:00–24:00 Jun 10 00:00–01:00, 16:00–17:00, 21:00–24:00 Jun 11 00:00–02:00, 16:00–17:00, 23:00–24:00 Jun 12 00:00–03:00, 14:00–17:00, 21:00–24:00 Jun 13 00:00–01:00, 15:00–17:00, 22:00–23:00 Jun 14 00:00–02:00, 16:00–19:00, 23:00–24:00 Jun 15 00:00–03:00 Jun 16 23:00–24:00 Jun 17 00:00–01:00, 18:00–23:00 Jun 21 16:00–20:00, 22:00–24:00 Jun 22 00:00–01:00, 20:00–24:00 Jun 23 00:00–01:00 Jun 24 22:00–24:00 Jun 25 16:00–18:00, 23:00–24:00 Jun 26 00:00–01:00, 16:00–17:00, 21:00–24:00 Jun 27 00:00–01:00, 23:00–24:00 Jun 28 00:00–02:00, 15:00–19:00, 22:00–24:00 Jun 29 00:00–03:00 Jun 30 15:00–21:00
July
Jul 2 17:00–20:00 Jul 3 17:00–22:00 Jul 4 20:00–24:00 Jul 8 00:00–03:00 Jul 9 15:00–17:00, 21:00–24:00 Jul 10 00:00–01:00, 17:00–18:00, 22:00–24:00 Jul 11 00:00–01:00, 23:00–24:00 Jul 12 00:00–03:00, 17:00–19:00, 23:00–24:00 Jul 13 00:00–03:00 Jul 14 23:00–24:00 Jul 15 00:00–02:00, 20:00–24:00 Jul 17 16:00–18:00, 22:00–24:00 Jul 18 00:00–01:00, 15:00–17:00, 21:00–24:00 Jul 19 00:00–01:00, 14:00–19:00, 22:00–24:00 Jul 21 16:00–17:00, 23:00–24:00 Jul 22 00:00–03:00, 15:00–18:00, 23:00–24:00 Jul 23 00:00–02:00, 20:00–24:00 Jul 24 16:00–17:00, 22:00–24:00 Jul 25 00:00–01:00, 21:00–24:00 Jul 26 00:00–01:00, 16:00–19:00, 22:00–24:00 Jul 27 00:00–01:00 Jul 28 22:00–24:00 Jul 29 00:00–01:00, 20:00–24:00 Jul 30 23:00–24:00 Jul 31 00:00–03:00, 15:00–17:00, 21:00–24:00
August
Aug 1 00:00–02:00, 22:00–24:00 Aug 2 00:00–01:00 Aug 6 19:00–21:00, 23:00–24:00 Aug 7 00:00–01:00 Aug 8 22:00–24:00 Aug 9 00:00–01:00, 16:00–17:00, 20:00–24:00 Aug 10 00:00–01:00, 14:00–15:00 Aug 11 20:00–24:00 Aug 12 16:00–18:00, 21:00–24:00 Aug 13 00:00–02:00, 16:00–17:00, 21:00–24:00 Aug 14 00:00–02:00 Aug 15 15:00–17:00, 19:00–22:00 Aug 19 23:00–24:00 Aug 20 00:00–02:00, 15:00–17:00, 21:00–24:00 Aug 21 00:00–01:00, 20:00–24:00 Aug 22 00:00–02:00, 15:00–17:00, 21:00–24:00 Aug 23 00:00–01:00, 16:00–18:00, 22:00–24:00 Aug 24 00:00–02:00 Aug 25 17:00–19:00, 23:00–24:00 Aug 26 00:00–02:00, 16:00–17:00, 20:00–24:00 Aug 27 15:00–17:00, 22:00–24:00 Aug 28 00:00–03:00, 20:00–24:00 Aug 29 00:00–01:00, 18:00–24:00 Aug 30 00:00–01:00, 16:00–18:00, 23:00–24:00 Aug 31 00:00–03:00
September
Sep 1 17:00–18:00 Sep 3 15:00–17:00, 23:00–24:00 Sep 4 00:00–02:00, 17:00–24:00 Sep 5 00:00–01:00, 15:00–18:00, 22:00–24:00 Sep 6 00:00–02:00, 17:00–19:00, 23:00–24:00 Sep 7 00:00–04:00 Sep 8 16:00–19:00, 23:00–24:00 Sep 9 00:00–01:00, 16:00–18:00, 21:00–24:00 Sep 10 00:00–02:00, 16:00–17:00, 22:00–24:00 Sep 11 00:00–02:00, 19:00–24:00 Sep 12 00:00–01:00, 14:00–17:00, 22:00–24:00 Sep 13 00:00–02:00 Sep 15 22:00–24:00 Sep 16 00:00–03:00 Sep 17 15:00–18:00, 22:00–24:00 Sep 18 00:00–02:00, 19:00–24:00 Sep 19 23:00–24:00 Sep 20 00:00–03:00, 17:00–19:00, 22:00–24:00 Sep 21 00:00–01:00 Sep 24 00:00–01:00, 15:00–16:00, 22:00–24:00 Sep 25 00:00–01:00, 18:00–22:00 Sep 26 15:00–18:00, 23:00–24:00 Sep 27 00:00–01:00, 16:00–19:00, 22:00–24:00 Sep 28 00:00–02:00 Sep 29 23:00–24:00 Sep 30 00:00–02:00, 15:00–17:00
October
Oct 1 00:00–03:00, 21:00–24:00 Oct 2 00:00–02:00, 17:00–18:00, 21:00–24:00 Oct 3 16:00–17:00, 23:00–24:00 Oct 4 00:00–02:00, 17:00–19:00, 22:00–24:00 Oct 5 00:00–02:00 Oct 6 23:00–24:00 Oct 7 19:00–21:00 Oct 8 22:00–24:00 Oct 9 00:00–02:00, 17:00–24:00 Oct 10 00:00–01:00, 16:00–18:00, 20:00–24:00 Oct 11 00:00–01:00, 18:00–19:00, 21:00–24:00 Oct 12 00:00–02:00 Oct 15 00:00–03:00, 15:00–17:00, 21:00–24:00 Oct 16 00:00–02:00, 22:00–24:00 Oct 17 00:00–02:00, 16:00–18:00, 22:00–24:00 Oct 18 00:00–02:00, 20:00–24:00 Oct 21 00:00–02:00 Oct 23 01:00–03:00, 16:00–19:00, 22:00–24:00 Oct 24 00:00–02:00, 15:00–17:00, 22:00–24:00 Oct 25 00:00–02:00, 17:00–19:00 Oct 28 00:00–02:00 Oct 30 22:00–24:00
November
Nov 1 20:00–21:00, 23:00–24:00 Nov 2 00:00–02:00 Nov 4 21:00–24:00 Nov 5 00:00–01:00, 21:00–23:00 Nov 6 21:00–24:00 Nov 7 23:00–24:00 Nov 8 00:00–03:00, 17:00–19:00 Nov 9 00:00–03:00 Nov 11 21:00–24:00 Nov 12 00:00–02:00, 22:00–24:00 Nov 13 00:00–01:00, 17:00–20:00, 22:00–24:00 Nov 14 21:00–24:00 Nov 15 00:00–02:00, 17:00–19:00, 23:00–24:00 Nov 16 00:00–02:00 Nov 20 17:00–24:00 Nov 21 00:00–01:00, 15:00–17:00 Nov 22 00:00–02:00, 15:00–19:00, 22:00–24:00 Nov 23 00:00–02:00 Nov 24 21:00–22:00 Nov 25 17:00–24:00 Nov 26 00:00–01:00, 21:00–24:00 Nov 27 00:00–01:00, 19:00–24:00 Nov 28 15:00–18:00 Nov 29 16:00–19:00 Nov 30 00:00–03:00
December
Dec 3 22:00–24:00 Dec 4 00:00–01:00, 21:00–24:00 Dec 5 17:00–19:00, 23:00–24:00 Dec 6 00:00–02:00, 21:00–24:00 Dec 7 00:00–02:00 Dec 9 22:00–24:00 Dec 10 00:00–01:00, 22:00–24:00 Dec 11 22:00–24:00 Dec 12 00:00–02:00, 20:00–24:00 Dec 13 00:00–01:00, 16:00–19:00 Dec 16 20:00–24:00 Dec 17 00:00–01:00, 18:00–24:00 Dec 18 20:00–24:00 Dec 19 00:00–02:00, 16:00–19:00, 22:00–24:00 Dec 20 00:00–01:00, 23:00–24:00 Dec 21 00:00–01:00 Dec 22 18:00–19:00, 21:00–24:00 Dec 23 00:00–01:00 Dec 27 17:00–18:00, 20:00–24:00 Dec 28 00:00–01:00, 16:00–21:00 Dec 30 16:00–17:00, 21:00–24:00 Dec 31 14:00–18:00