Most often in November, 30 days.
Highest follower count seen that year: 25,678.
January
Jan 3 03:00–08:00, 18:00–20:00 Jan 4 03:00–06:00 Jan 5 03:00–05:00 Jan 6 17:00–19:00 Jan 7 03:00–05:00 Jan 10 05:00–06:00 Jan 12 16:00–21:00 Jan 14 03:00–07:00 Jan 16 03:00–05:00, 16:00–20:00 Jan 17 04:00–08:00, 16:00–17:00 Jan 18 03:00–06:00, 16:00–19:00 Jan 21 03:00–06:00 Jan 22 16:00–17:00 Jan 23 16:00–19:00 Jan 24 16:00–17:00 Jan 25 04:00–05:00, 16:00–19:00 Jan 29 17:00–20:00 Jan 30 15:00–20:00
February
Feb 1 03:00–06:00 Feb 3 21:00–24:00 Feb 4 21:00–23:00 Feb 5 17:00–18:00 Feb 6 19:00–21:00 Feb 7 16:00–20:00 Feb 8 22:00–23:00 Feb 14 18:00–21:00 Feb 17 17:00–19:00 Feb 20 16:00–19:00 Feb 21 20:00–24:00 Feb 22 21:00–23:00 Feb 23 18:00–23:00 Feb 24 22:00–24:00 Feb 25 00:00–01:00 Feb 27 22:00–24:00 Feb 28 00:00–01:00, 15:00–20:00
March
Mar 1 20:00–23:00 Mar 2 19:00–23:00 Mar 3 21:00–24:00 Mar 6 23:00–24:00 Mar 7 00:00–04:00, 17:00–22:00 Mar 8 21:00–24:00 Mar 9 18:00–22:00 Mar 10 17:00–20:00 Mar 13 16:00–19:00 Mar 14 21:00–24:00 Mar 15 00:00–01:00, 21:00–24:00 Mar 16 17:00–22:00 Mar 17 17:00–20:00 Mar 19 02:00–04:00, 21:00–24:00 Mar 21 02:00–06:00, 16:00–21:00 Mar 22 21:00–24:00 Mar 23 20:00–23:00 Mar 24 19:00–22:00 Mar 27 19:00–23:00 Mar 29 22:00–24:00 Mar 30 00:00–01:00, 19:00–24:00 Mar 31 16:00–20:00
April
Apr 3 03:00–06:00 Apr 4 02:00–05:00, 16:00–19:00 Apr 5 03:00–05:00, 20:00–23:00 Apr 6 03:00–07:00, 18:00–21:00 Apr 8 03:00–05:00 Apr 10 02:00–06:00, 18:00–20:00 Apr 11 03:00–07:00 Apr 12 02:00–03:00 Apr 13 02:00–07:00, 17:00–20:00 Apr 14 02:00–06:00, 21:00–24:00 Apr 16 16:00–18:00 Apr 17 21:00–23:00 Apr 18 16:00–19:00 Apr 19 20:00–22:00 Apr 20 20:00–23:00 Apr 21 22:00–24:00 Apr 24 03:00–05:00, 21:00–24:00 Apr 25 17:00–20:00 Apr 26 20:00–23:00 Apr 27 03:00–06:00, 20:00–22:00 Apr 30 19:00–21:00
May
May 1 15:00–19:00 May 3 00:00–02:00 May 4 04:00–07:00, 16:00–19:00 May 5 22:00–24:00 May 8 02:00–05:00, 15:00–17:00 May 10 00:00–02:00, 22:00–24:00 May 11 00:00–01:00, 15:00–18:00 May 12 14:00–18:00 May 14 15:00–18:00 May 15 15:00–19:00 May 16 15:00–16:00 May 17 04:00–07:00, 21:00–23:00 May 18 17:00–20:00 May 19 23:00–24:00 May 20 00:00–01:00 May 21 20:00–23:00 May 24 03:00–04:00 May 25 02:00–03:00 May 28 23:00–24:00 May 29 00:00–01:00, 19:00–22:00 May 30 15:00–19:00 May 31 21:00–24:00
June
Jun 1 21:00–23:00 Jun 2 16:00–19:00 Jun 4 14:00–18:00 Jun 6 15:00–16:00, 18:00–19:00, 23:00–24:00 Jun 7 00:00–02:00, 22:00–24:00 Jun 8 15:00–17:00 Jun 9 15:00–19:00 Jun 11 21:00–24:00 Jun 12 20:00–24:00 Jun 13 23:00–24:00 Jun 14 00:00–03:00, 21:00–24:00 Jun 15 00:00–01:00, 20:00–24:00 Jun 16 21:00–23:00 Jun 18 23:00–24:00 Jun 19 00:00–01:00, 15:00–19:00, 22:00–24:00 Jun 21 00:00–02:00, 22:00–24:00 Jun 22 00:00–01:00, 17:00–21:00 Jun 25 14:00–19:00 Jun 28 16:00–20:00 Jun 29 03:00–06:00
July
Jul 1 15:00–19:00 Jul 2 02:00–06:00, 16:00–19:00 Jul 3 04:00–07:00, 17:00–22:00 Jul 4 15:00–20:00 Jul 5 02:00–05:00, 17:00–20:00 Jul 6 15:00–19:00 Jul 7 16:00–19:00 Jul 9 21:00–24:00 Jul 10 00:00–01:00, 16:00–20:00 Jul 11 16:00–19:00 Jul 12 04:00–07:00, 23:00–24:00 Jul 13 00:00–02:00, 21:00–22:00 Jul 14 21:00–24:00 Jul 16 21:00–23:00 Jul 17 21:00–23:00 Jul 18 23:00–24:00 Jul 19 00:00–03:00, 21:00–24:00 Jul 20 00:00–01:00 Jul 21 15:00–19:00, 22:00–24:00 Jul 22 00:00–01:00 Jul 23 16:00–20:00 Jul 24 03:00–05:00, 15:00–17:00, 21:00–24:00 Jul 25 15:00–18:00 Jul 29 02:00–05:00 Jul 30 21:00–23:00
August
Aug 5 16:00–18:00 Aug 7 22:00–24:00 Aug 8 00:00–01:00, 15:00–19:00 Aug 9 02:00–05:00, 16:00–18:00 Aug 10 17:00–19:00, 22:00–24:00 Aug 11 00:00–01:00, 16:00–18:00 Aug 12 04:00–05:00 Aug 13 03:00–04:00, 14:00–17:00 Aug 15 15:00–18:00 Aug 16 03:00–07:00, 20:00–23:00 Aug 17 22:00–24:00 Aug 19 16:00–18:00, 23:00–24:00 Aug 20 00:00–02:00 Aug 21 15:00–18:00 Aug 22 03:00–07:00, 16:00–19:00 Aug 23 02:00–04:00, 16:00–19:00 Aug 24 17:00–21:00 Aug 25 03:00–05:00 Aug 26 02:00–06:00 Aug 27 01:00–04:00 Aug 28 03:00–06:00, 21:00–24:00 Aug 29 02:00–05:00, 19:00–23:00 Aug 30 03:00–05:00, 21:00–24:00 Aug 31 02:00–05:00, 21:00–24:00
September
Sep 1 00:00–01:00, 19:00–22:00 Sep 4 20:00–23:00 Sep 5 15:00–18:00 Sep 6 03:00–06:00, 21:00–23:00 Sep 7 03:00–05:00, 16:00–19:00, 21:00–24:00 Sep 8 00:00–01:00, 15:00–18:00 Sep 9 03:00–05:00 Sep 10 02:00–05:00 Sep 11 03:00–06:00, 22:00–23:00 Sep 12 03:00–05:00 Sep 13 03:00–06:00, 15:00–18:00 Sep 14 03:00–05:00 Sep 15 02:00–06:00, 21:00–24:00 Sep 16 20:00–23:00 Sep 17 03:00–05:00 Sep 18 21:00–24:00 Sep 20 02:00–04:00, 19:00–21:00 Sep 21 05:00–09:00 Sep 22 04:00–06:00, 21:00–23:00 Sep 23 03:00–05:00 Sep 26 15:00–17:00 Sep 28 02:00–03:00
October
Oct 2 15:00–18:00 Oct 3 04:00–05:00, 19:00–23:00 Oct 4 21:00–24:00 Oct 5 03:00–06:00, 21:00–24:00 Oct 6 00:00–01:00, 21:00–23:00 Oct 7 21:00–23:00 Oct 10 01:00–05:00, 16:00–19:00 Oct 11 02:00–06:00, 16:00–19:00 Oct 12 03:00–06:00, 16:00–19:00, 22:00–24:00 Oct 13 03:00–06:00, 16:00–18:00 Oct 15 03:00–06:00 Oct 16 02:00–04:00, 20:00–23:00 Oct 17 02:00–04:00, 21:00–24:00 Oct 18 03:00–06:00, 21:00–24:00 Oct 19 03:00–05:00, 16:00–18:00 Oct 21 16:00–18:00 Oct 23 19:00–21:00 Oct 24 03:00–04:00, 17:00–19:00, 23:00–24:00 Oct 25 00:00–02:00, 16:00–19:00 Oct 26 03:00–06:00, 15:00–18:00 Oct 27 14:00–18:00 Oct 28 03:00–05:00, 16:00–19:00 Oct 29 02:00–05:00 Oct 30 02:00–05:00, 15:00–17:00 Oct 31 03:00–06:00, 21:00–24:00
November
Nov 1 00:00–01:00, 03:00–06:00, 21:00–23:00 Nov 2 16:00–18:00, 22:00–24:00 Nov 3 00:00–01:00, 21:00–24:00 Nov 4 21:00–24:00 Nov 5 22:00–24:00 Nov 6 00:00–01:00 Nov 7 03:00–06:00, 21:00–24:00 Nov 8 04:00–06:00, 22:00–24:00 Nov 9 16:00–18:00, 21:00–24:00 Nov 10 00:00–01:00, 20:00–23:00 Nov 11 02:00–04:00, 16:00–18:00 Nov 12 03:00–06:00 Nov 13 21:00–23:00 Nov 14 03:00–06:00, 21:00–23:00 Nov 15 02:00–06:00, 21:00–23:00 Nov 16 03:00–05:00, 21:00–24:00 Nov 17 00:00–01:00 Nov 18 03:00–06:00, 20:00–23:00 Nov 19 02:00–04:00 Nov 20 22:00–24:00 Nov 21 03:00–06:00 Nov 22 01:00–05:00, 21:00–24:00 Nov 23 00:00–03:00, 22:00–24:00 Nov 24 00:00–01:00, 21:00–24:00 Nov 25 03:00–04:00 Nov 26 03:00–06:00, 15:00–17:00 Nov 27 21:00–24:00 Nov 28 02:00–06:00, 23:00–24:00 Nov 29 00:00–01:00, 03:00–06:00, 22:00–24:00 Nov 30 00:00–01:00, 03:00–06:00, 15:00–16:00
December
Dec 2 00:00–01:00 Dec 5 22:00–24:00 Dec 6 21:00–24:00 Dec 7 02:00–04:00, 16:00–19:00, 22:00–24:00 Dec 8 21:00–24:00 Dec 9 03:00–05:00, 15:00–17:00, 22:00–24:00 Dec 10 00:00–01:00, 03:00–05:00, 15:00–17:00 Dec 12 02:00–04:00, 22:00–24:00 Dec 13 00:00–01:00, 03:00–05:00, 16:00–18:00 Dec 14 02:00–05:00, 17:00–19:00, 21:00–24:00 Dec 15 18:00–20:00 Dec 16 03:00–05:00, 14:00–17:00 Dec 17 02:00–05:00 Dec 18 02:00–05:00, 20:00–22:00 Dec 19 03:00–05:00, 16:00–20:00 Dec 20 01:00–06:00, 16:00–19:00 Dec 21 18:00–21:00 Dec 22 01:00–03:00, 21:00–24:00 Dec 23 03:00–06:00 Dec 24 16:00–18:00 Dec 25 02:00–05:00, 19:00–22:00 Dec 26 17:00–19:00 Dec 27 03:00–06:00 Dec 28 19:00–22:00 Dec 29 21:00–24:00 Dec 31 03:00–05:00