Most often in March, 28 days.
Highest follower count seen that year: 18,120.
January
Jan 1 05:00–06:00 Jan 2 00:00–04:00, 11:00–12:00 Jan 3 02:00–04:00, 09:00–10:00 Jan 4 02:00–03:00, 11:00–12:00, 22:00–23:00 Jan 5 04:00–05:00, 22:00–23:00 Jan 6 22:00–23:00 Jan 8 22:00–23:00 Jan 9 11:00–12:00 Jan 10 11:00–13:00, 22:00–23:00 Jan 11 07:00–08:00 Jan 12 00:00–02:00, 05:00–06:00, 22:00–23:00 Jan 14 21:00–24:00 Jan 15 11:00–12:00 Jan 16 22:00–23:00 Jan 18 02:00–06:00, 10:00–11:00 Jan 19 01:00–03:00, 06:00–07:00, 21:00–22:00 Jan 20 23:00–24:00 Jan 21 11:00–12:00, 21:00–22:00 Jan 22 11:00–12:00, 22:00–23:00 Jan 23 21:00–22:00 Jan 24 22:00–23:00 Jan 25 04:00–06:00, 10:00–11:00, 21:00–23:00 Jan 26 00:00–02:00, 06:00–08:00, 11:00–12:00 Jan 27 03:00–04:00, 07:00–08:00, 21:00–22:00 Jan 28 11:00–12:00 Jan 31 23:00–24:00
February
Feb 2 04:00–05:00, 21:00–22:00 Feb 6 21:00–22:00 Feb 8 03:00–04:00, 11:00–12:00 Feb 9 04:00–05:00, 09:00–10:00, 21:00–23:00 Feb 10 11:00–13:00, 23:00–24:00 Feb 11 12:00–13:00, 23:00–24:00 Feb 12 22:00–23:00 Feb 13 23:00–24:00 Feb 14 09:00–10:00, 20:00–21:00 Feb 15 04:00–05:00 Feb 16 04:00–05:00, 12:00–13:00, 22:00–23:00 Feb 17 23:00–24:00 Feb 18 11:00–12:00, 22:00–24:00 Feb 19 11:00–12:00 Feb 20 11:00–12:00, 23:00–24:00 Feb 21 21:00–22:00 Feb 22 05:00–06:00 Feb 23 00:00–01:00, 10:00–11:00, 22:00–23:00 Feb 24 23:00–24:00 Feb 26 11:00–12:00, 23:00–24:00 Feb 27 11:00–12:00 Feb 28 07:00–08:00, 12:00–14:00
March
Mar 1 03:00–04:00 Mar 2 01:00–02:00, 05:00–06:00, 11:00–12:00, 22:00–23:00 Mar 3 22:00–23:00 Mar 4 23:00–24:00 Mar 5 11:00–13:00, 21:00–23:00 Mar 6 12:00–13:00, 23:00–24:00 Mar 7 11:00–13:00 Mar 9 04:00–06:00, 10:00–11:00, 21:00–23:00 Mar 10 00:00–01:00, 11:00–12:00, 22:00–24:00 Mar 11 11:00–13:00, 23:00–24:00 Mar 12 00:00–01:00, 11:00–13:00, 21:00–22:00 Mar 13 23:00–24:00 Mar 14 12:00–13:00 Mar 15 04:00–05:00 Mar 16 01:00–03:00, 11:00–12:00, 21:00–23:00 Mar 17 11:00–12:00, 21:00–22:00 Mar 18 23:00–24:00 Mar 19 00:00–01:00, 11:00–12:00, 21:00–23:00 Mar 20 00:00–01:00, 12:00–13:00 Mar 21 11:00–13:00, 21:00–22:00 Mar 23 09:00–12:00, 21:00–24:00 Mar 24 11:00–13:00, 22:00–23:00 Mar 25 00:00–01:00, 11:00–12:00 Mar 26 11:00–13:00, 21:00–24:00 Mar 27 00:00–01:00, 12:00–13:00 Mar 28 11:00–13:00 Mar 30 03:00–05:00, 09:00–13:00, 22:00–24:00 Mar 31 00:00–01:00, 12:00–13:00, 21:00–23:00
April
Apr 1 21:00–24:00 Apr 2 11:00–13:00, 21:00–24:00 Apr 4 00:00–01:00, 21:00–22:00 Apr 5 02:00–04:00, 10:00–13:00 Apr 6 03:00–04:00, 11:00–12:00 Apr 7 01:00–02:00 Apr 8 01:00–02:00 Apr 9 00:00–01:00, 22:00–24:00 Apr 10 00:00–03:00 Apr 11 01:00–02:00, 13:00–15:00 Apr 12 04:00–05:00, 12:00–13:00 Apr 13 02:00–05:00, 10:00–12:00, 22:00–23:00 Apr 14 00:00–01:00, 23:00–24:00 Apr 16 01:00–02:00 Apr 17 00:00–04:00 Apr 18 01:00–05:00, 08:00–09:00, 23:00–24:00 Apr 19 05:00–06:00 Apr 20 09:00–11:00, 22:00–24:00 Apr 21 04:00–05:00, 11:00–13:00 Apr 22 01:00–03:00, 06:00–08:00, 11:00–12:00 Apr 23 05:00–07:00 Apr 24 04:00–05:00 Apr 25 03:00–04:00, 23:00–24:00 Apr 26 03:00–04:00, 09:00–10:00, 12:00–14:00 Apr 27 02:00–03:00, 09:00–11:00, 23:00–24:00 Apr 28 01:00–02:00 Apr 29 00:00–01:00, 22:00–23:00 Apr 30 00:00–01:00
May
May 1 00:00–02:00, 22:00–23:00 May 2 12:00–14:00 May 4 09:00–11:00, 22:00–23:00 May 5 22:00–24:00 May 6 00:00–02:00 May 7 12:00–13:00, 22:00–24:00 May 9 02:00–03:00 May 10 05:00–06:00 May 11 06:00–10:00 May 12 00:00–01:00, 22:00–23:00 May 13 00:00–02:00, 12:00–13:00 May 14 00:00–02:00, 12:00–14:00, 22:00–23:00 May 15 00:00–01:00 May 16 00:00–02:00, 12:00–14:00 May 17 03:00–06:00 May 18 00:00–01:00, 05:00–06:00, 22:00–24:00 May 19 22:00–24:00 May 21 00:00–01:00, 22:00–23:00 May 22 12:00–13:00 May 23 00:00–01:00, 12:00–13:00 May 24 01:00–02:00 May 25 06:00–10:00 May 26 00:00–01:00, 12:00–14:00, 22:00–23:00 May 27 00:00–01:00 May 28 00:00–01:00, 12:00–14:00, 22:00–23:00 May 29 00:00–01:00 May 30 00:00–01:00, 23:00–24:00 May 31 02:00–09:00
June
Jun 1 06:00–07:00, 22:00–24:00 Jun 2 00:00–01:00, 13:00–14:00, 22:00–23:00 Jun 3 00:00–01:00 Jun 4 00:00–02:00, 12:00–14:00, 22:00–23:00 Jun 5 00:00–01:00 Jun 6 00:00–02:00 Jun 9 01:00–02:00, 08:00–09:00 Jun 10 00:00–01:00, 12:00–14:00 Jun 11 00:00–01:00 Jun 12 00:00–01:00 Jun 15 06:00–07:00, 11:00–13:00 Jun 20 00:00–01:00 Jun 22 04:00–07:00 Jun 23 12:00–13:00, 23:00–24:00 Jun 24 13:00–14:00 Jun 25 01:00–02:00, 23:00–24:00 Jun 26 00:00–01:00 Jun 27 00:00–02:00
July
Jul 1 01:00–02:00, 23:00–24:00 Jul 2 00:00–01:00 Jul 3 00:00–01:00, 23:00–24:00 Jul 22 23:00–24:00 Jul 27 06:00–07:00
August
Aug 10 04:00–05:00 Aug 11 00:00–01:00, 04:00–05:00 Aug 12 04:00–05:00, 07:00–08:00 Aug 14 03:00–04:00, 07:00–09:00 Aug 16 04:00–06:00 Aug 17 12:00–13:00 Aug 18 00:00–01:00, 22:00–23:00 Aug 19 01:00–02:00 Aug 20 23:00–24:00 Aug 23 00:00–01:00 Aug 24 06:00–07:00 Aug 25 01:00–02:00, 23:00–24:00 Aug 27 01:00–02:00 Aug 28 00:00–01:00 Aug 30 22:00–23:00 Aug 31 06:00–08:00
September
Sep 1 00:00–01:00
October
Oct 5 04:00–05:00 Oct 8 00:00–01:00 Oct 11 03:00–04:00
November
Nov 9 05:00–06:00, 22:00–23:00 Nov 12 23:00–24:00 Nov 16 04:00–06:00 Nov 18 04:00–06:00 Nov 23 05:00–06:00, 22:00–23:00 Nov 25 22:00–23:00 Nov 30 02:00–03:00, 05:00–06:00
December
Dec 1 04:00–05:00 Dec 4 22:00–23:00 Dec 5 12:00–13:00, 22:00–23:00 Dec 7 09:00–10:00 Dec 8 23:00–24:00 Dec 10 23:00–24:00 Dec 11 21:00–23:00 Dec 12 01:00–02:00 Dec 13 03:00–06:00 Dec 14 02:00–03:00, 05:00–06:00, 09:00–11:00 Dec 15 22:00–23:00 Dec 16 23:00–24:00 Dec 17 21:00–24:00 Dec 18 23:00–24:00 Dec 19 11:00–12:00, 22:00–23:00 Dec 20 02:00–03:00, 20:00–22:00 Dec 21 03:00–06:00 Dec 23 00:00–01:00, 11:00–12:00 Dec 24 00:00–01:00, 07:00–08:00 Dec 26 00:00–03:00, 07:00–08:00 Dec 27 03:00–04:00 Dec 28 03:00–06:00, 08:00–09:00 Dec 29 00:00–01:00 Dec 30 11:00–12:00, 21:00–22:00 Dec 31 08:00–10:00