Most often in March, 27 days.
Highest follower count seen that year: 30,314.
January
Jan 2 13:00–17:00, 22:00–24:00 Jan 3 00:00–02:00, 14:00–16:00, 23:00–24:00 Jan 4 00:00–02:00 Jan 5 23:00–24:00 Jan 6 00:00–02:00, 22:00–24:00 Jan 7 00:00–02:00, 12:00–15:00, 21:00–22:00 Jan 8 00:00–01:00 Jan 10 15:00–18:00 Jan 12 23:00–24:00 Jan 13 00:00–02:00, 23:00–24:00 Jan 14 00:00–03:00, 13:00–16:00, 22:00–24:00 Jan 15 00:00–02:00 Jan 17 16:00–19:00 Jan 19 22:00–24:00 Jan 20 00:00–03:00 Jan 21 12:00–15:00, 22:00–24:00 Jan 22 00:00–02:00, 22:00–24:00 Jan 23 00:00–01:00, 13:00–16:00 Jan 24 16:00–18:00 Jan 26 22:00–24:00 Jan 27 00:00–01:00 Jan 28 22:00–24:00 Jan 29 00:00–01:00
February
Feb 1 23:00–24:00 Feb 2 00:00–02:00, 22:00–24:00 Feb 3 00:00–03:00 Feb 6 22:00–24:00 Feb 7 00:00–01:00, 23:00–24:00 Feb 8 00:00–02:00, 23:00–24:00 Feb 9 00:00–03:00, 22:00–24:00 Feb 10 00:00–01:00 Feb 11 22:00–24:00 Feb 12 00:00–01:00, 22:00–24:00 Feb 13 00:00–02:00, 23:00–24:00 Feb 14 00:00–03:00, 22:00–24:00 Feb 15 00:00–04:00 Feb 17 22:00–24:00 Feb 18 00:00–03:00, 22:00–24:00 Feb 19 00:00–02:00, 22:00–24:00 Feb 20 00:00–02:00, 22:00–24:00 Feb 21 00:00–02:00 Feb 22 00:00–02:00 Feb 24 22:00–24:00 Feb 25 00:00–01:00, 22:00–24:00 Feb 26 00:00–02:00, 23:00–24:00 Feb 27 00:00–02:00, 23:00–24:00 Feb 28 00:00–02:00
March
Mar 2 23:00–24:00 Mar 3 00:00–03:00, 22:00–24:00 Mar 4 00:00–02:00, 22:00–24:00 Mar 5 00:00–02:00, 23:00–24:00 Mar 6 00:00–02:00, 22:00–24:00 Mar 7 00:00–02:00 Mar 9 22:00–24:00 Mar 10 00:00–03:00, 22:00–24:00 Mar 11 00:00–02:00, 22:00–24:00 Mar 12 00:00–03:00, 22:00–24:00 Mar 13 00:00–03:00, 22:00–24:00 Mar 14 00:00–01:00, 15:00–18:00 Mar 16 23:00–24:00 Mar 17 00:00–02:00, 22:00–24:00 Mar 18 00:00–01:00, 22:00–24:00 Mar 19 00:00–01:00, 22:00–24:00 Mar 20 00:00–02:00, 23:00–24:00 Mar 21 00:00–02:00, 22:00–24:00 Mar 22 00:00–02:00 Mar 24 22:00–24:00 Mar 25 00:00–02:00 Mar 26 22:00–24:00 Mar 27 00:00–01:00, 23:00–24:00 Mar 28 00:00–04:00 Mar 29 23:00–24:00 Mar 30 00:00–03:00, 22:00–24:00 Mar 31 22:00–24:00
April
Apr 1 00:00–01:00, 22:00–24:00 Apr 2 00:00–01:00, 21:00–24:00 Apr 3 21:00–24:00 Apr 4 00:00–01:00, 16:00–18:00, 21:00–23:00 Apr 6 21:00–24:00 Apr 7 21:00–24:00 Apr 8 00:00–01:00, 22:00–24:00 Apr 9 21:00–24:00 Apr 10 00:00–01:00 Apr 11 16:00–18:00, 22:00–24:00 Apr 12 00:00–02:00 Apr 13 22:00–24:00 Apr 14 00:00–01:00 Apr 15 21:00–24:00 Apr 16 00:00–01:00, 22:00–24:00 Apr 17 00:00–01:00, 22:00–24:00 Apr 18 00:00–01:00 Apr 20 22:00–24:00 Apr 21 00:00–01:00, 15:00–17:00, 22:00–24:00 Apr 22 00:00–01:00, 22:00–24:00 Apr 23 00:00–01:00, 22:00–24:00 Apr 24 00:00–01:00 Apr 25 22:00–23:00 Apr 26 00:00–02:00 Apr 27 23:00–24:00 Apr 28 00:00–02:00
May
May 5 22:00–24:00 May 6 00:00–02:00, 14:00–17:00, 22:00–24:00 May 7 00:00–01:00, 22:00–24:00 May 8 00:00–01:00, 22:00–24:00 May 9 00:00–01:00, 21:00–24:00 May 10 00:00–02:00 May 11 22:00–24:00 May 12 00:00–01:00, 23:00–24:00 May 13 21:00–24:00 May 14 22:00–24:00 May 15 00:00–01:00, 23:00–24:00 May 16 00:00–01:00 May 18 22:00–24:00 May 19 22:00–23:00 May 20 21:00–24:00 May 21 00:00–01:00, 22:00–24:00 May 22 00:00–01:00, 23:00–24:00 May 23 00:00–02:00, 22:00–24:00 May 24 00:00–02:00 May 25 22:00–24:00 May 26 00:00–02:00, 23:00–24:00 May 27 22:00–24:00 May 28 00:00–02:00, 23:00–24:00 May 29 00:00–03:00
June
Jun 1 00:00–03:00, 22:00–24:00 Jun 2 00:00–01:00 Jun 4 21:00–24:00 Jun 5 21:00–24:00 Jun 6 00:00–01:00 Jun 8 21:00–24:00 Jun 9 00:00–01:00 Jun 10 21:00–24:00 Jun 11 21:00–24:00 Jun 12 21:00–23:00 Jun 13 23:00–24:00 Jun 14 00:00–02:00 Jun 17 22:00–24:00 Jun 18 00:00–02:00, 22:00–24:00 Jun 19 00:00–01:00, 22:00–24:00 Jun 20 00:00–03:00 Jun 29 21:00–24:00 Jun 30 00:00–02:00, 22:00–24:00
July
Jul 1 22:00–24:00 Jul 2 00:00–01:00, 22:00–24:00 Jul 3 00:00–01:00, 22:00–24:00 Jul 4 00:00–01:00, 22:00–24:00 Jul 5 00:00–01:00, 22:00–24:00 Jul 6 00:00–02:00 Jul 24 22:00–24:00 Jul 25 00:00–02:00, 22:00–24:00 Jul 26 00:00–02:00, 23:00–24:00 Jul 27 00:00–04:00, 23:00–24:00 Jul 28 00:00–01:00 Jul 30 22:00–24:00 Jul 31 00:00–01:00, 23:00–24:00
August
Aug 1 00:00–02:00, 22:00–24:00 Aug 2 00:00–02:00 Aug 3 22:00–24:00 Aug 4 00:00–02:00, 22:00–24:00 Aug 5 00:00–01:00, 22:00–24:00 Aug 6 00:00–01:00, 22:00–24:00 Aug 7 00:00–03:00, 22:00–24:00 Aug 8 00:00–01:00 Aug 11 22:00–24:00 Aug 12 00:00–01:00, 22:00–23:00 Aug 13 00:00–03:00, 22:00–23:00 Aug 14 00:00–02:00, 23:00–24:00 Aug 15 00:00–03:00, 22:00–24:00 Aug 16 00:00–01:00, 23:00–24:00 Aug 17 00:00–04:00, 23:00–24:00 Aug 18 00:00–02:00 Aug 26 22:00–24:00 Aug 27 00:00–02:00, 23:00–24:00 Aug 28 22:00–24:00 Aug 29 00:00–02:00, 22:00–24:00 Aug 30 00:00–02:00 Aug 31 22:00–24:00
September
Sep 1 00:00–02:00, 22:00–24:00 Sep 2 00:00–01:00 Sep 4 22:00–24:00 Sep 5 00:00–01:00 Sep 7 22:00–24:00 Sep 8 00:00–02:00, 22:00–24:00 Sep 9 00:00–02:00, 22:00–24:00 Sep 10 00:00–01:00, 23:00–24:00 Sep 11 00:00–02:00, 21:00–24:00 Sep 12 00:00–01:00, 22:00–24:00 Sep 13 22:00–24:00 Sep 14 00:00–01:00, 21:00–24:00 Sep 15 00:00–02:00 Sep 17 23:00–24:00 Sep 18 00:00–01:00 Sep 22 21:00–24:00 Sep 23 22:00–24:00 Sep 24 00:00–01:00, 21:00–24:00 Sep 25 00:00–01:00 Sep 26 23:00–24:00 Sep 27 00:00–01:00 Sep 29 22:00–24:00 Sep 30 00:00–01:00
October
Oct 2 22:00–24:00 Oct 3 00:00–01:00, 22:00–24:00 Oct 4 00:00–01:00 Oct 5 22:00–24:00 Oct 6 00:00–02:00, 22:00–24:00 Oct 7 00:00–01:00, 22:00–24:00 Oct 8 00:00–01:00, 22:00–24:00 Oct 9 00:00–02:00, 22:00–24:00 Oct 10 00:00–01:00, 23:00–24:00 Oct 11 00:00–01:00 Oct 12 22:00–24:00 Oct 13 00:00–02:00, 22:00–24:00 Oct 14 00:00–02:00, 22:00–24:00 Oct 15 00:00–01:00, 22:00–24:00 Oct 16 21:00–24:00 Oct 17 00:00–02:00 Oct 18 22:00–24:00 Oct 19 00:00–03:00, 22:00–24:00 Oct 20 00:00–01:00 Oct 22 22:00–24:00 Oct 23 00:00–01:00, 22:00–24:00 Oct 24 00:00–01:00, 22:00–24:00 Oct 25 00:00–01:00, 22:00–24:00
November
Nov 1 00:00–02:00 Nov 2 22:00–24:00 Nov 3 00:00–03:00, 23:00–24:00 Nov 4 00:00–01:00, 23:00–24:00 Nov 5 00:00–02:00, 23:00–24:00 Nov 6 00:00–01:00, 23:00–24:00 Nov 7 00:00–02:00 Nov 8 00:00–03:00, 23:00–24:00 Nov 9 00:00–02:00 Nov 15 00:00–03:00 Nov 16 22:00–24:00 Nov 17 00:00–02:00, 22:00–24:00 Nov 18 00:00–01:00, 23:00–24:00 Nov 19 00:00–02:00, 22:00–24:00 Nov 20 00:00–01:00, 23:00–24:00 Nov 21 00:00–02:00 Nov 22 00:00–02:00
December
Dec 1 22:00–24:00 Dec 2 00:00–01:00, 23:00–24:00 Dec 3 00:00–02:00, 23:00–24:00 Dec 4 00:00–02:00, 23:00–24:00 Dec 5 00:00–02:00 Dec 6 00:00–03:00 Dec 7 22:00–24:00 Dec 8 00:00–02:00 Dec 9 23:00–24:00 Dec 10 00:00–02:00, 23:00–24:00 Dec 11 00:00–01:00 Dec 12 00:00–02:00 Dec 13 00:00–02:00 Dec 14 23:00–24:00 Dec 15 00:00–01:00, 23:00–24:00 Dec 16 00:00–02:00, 11:00–15:00 Dec 17 12:00–15:00, 23:00–24:00 Dec 18 00:00–02:00, 12:00–13:00 Dec 19 10:00–13:00, 17:00–19:00 Dec 20 00:00–02:00 Dec 27 00:00–04:00 Dec 28 00:00–02:00, 15:00–18:00 Dec 29 00:00–05:00, 15:00–17:00, 23:00–24:00 Dec 30 00:00–04:00, 23:00–24:00 Dec 31 00:00–02:00, 14:00–16:00