Most often in January, 27 days.
Highest follower count seen that year: 8,288.
January
Jan 2 12:00–13:00 Jan 3 07:00–08:00, 10:00–12:00 Jan 5 07:00–09:00, 12:00–14:00 Jan 7 05:00–07:00 Jan 8 10:00–11:00, 17:00–19:00 Jan 9 05:00–12:00, 17:00–18:00 Jan 10 03:00–04:00, 09:00–10:00 Jan 11 07:00–09:00, 11:00–14:00 Jan 12 02:00–03:00, 08:00–11:00 Jan 13 04:00–05:00, 07:00–12:00, 15:00–16:00 Jan 14 06:00–10:00, 15:00–16:00 Jan 15 11:00–12:00, 15:00–16:00 Jan 16 03:00–11:00 Jan 17 03:00–08:00 Jan 18 03:00–08:00 Jan 19 09:00–17:00 Jan 20 04:00–05:00, 12:00–15:00 Jan 21 07:00–13:00 Jan 22 08:00–09:00 Jan 23 05:00–07:00, 11:00–16:00 Jan 25 14:00–16:00 Jan 26 10:00–12:00, 16:00–20:00 Jan 27 03:00–09:00 Jan 28 03:00–06:00, 08:00–10:00 Jan 29 03:00–08:00 Jan 30 03:00–06:00 Jan 31 03:00–07:00, 11:00–12:00
February
Feb 1 07:00–15:00 Feb 2 04:00–05:00, 10:00–14:00 Feb 3 03:00–06:00, 08:00–10:00, 12:00–13:00 Feb 4 03:00–13:00 Feb 5 06:00–09:00, 11:00–12:00 Feb 6 07:00–11:00 Feb 7 03:00–06:00, 08:00–09:00 Feb 9 10:00–14:00 Feb 10 04:00–11:00 Feb 11 03:00–08:00, 13:00–14:00 Feb 13 03:00–05:00, 07:00–09:00 Feb 14 03:00–05:00 Feb 15 16:00–17:00 Feb 16 11:00–12:00 Feb 17 07:00–14:00 Feb 18 08:00–10:00, 12:00–13:00 Feb 19 03:00–05:00 Feb 20 03:00–05:00 Feb 21 03:00–04:00 Feb 25 04:00–05:00, 08:00–12:00 Feb 26 04:00–05:00, 07:00–09:00 Feb 27 03:00–04:00, 13:00–16:00 Feb 28 03:00–10:00
March
Mar 1 08:00–10:00 Mar 2 12:00–15:00 Mar 3 05:00–08:00, 10:00–14:00 Mar 4 06:00–14:00 Mar 5 06:00–09:00 Mar 6 03:00–05:00, 07:00–09:00 Mar 7 07:00–09:00 Mar 8 07:00–10:00 Mar 9 12:00–13:00 Mar 10 05:00–13:00 Mar 11 05:00–08:00 Mar 12 05:00–09:00, 12:00–13:00 Mar 13 06:00–09:00 Mar 14 07:00–09:00 Mar 15 11:00–12:00 Mar 16 04:00–07:00, 11:00–14:00, 17:00–18:00 Mar 17 02:00–04:00, 08:00–10:00 Mar 18 05:00–06:00, 10:00–11:00 Mar 19 03:00–05:00, 08:00–13:00 Mar 24 06:00–08:00 Mar 25 05:00–07:00 Mar 26 05:00–07:00
April
Apr 2 04:00–10:00 Apr 3 07:00–08:00, 10:00–11:00 Apr 4 04:00–08:00, 11:00–12:00 Apr 5 02:00–06:00, 08:00–09:00 Apr 7 06:00–07:00 Apr 8 13:00–14:00 Apr 9 02:00–06:00 Apr 17 04:00–08:00 Apr 18 05:00–06:00 Apr 28 09:00–10:00 Apr 29 06:00–07:00, 09:00–10:00 Apr 30 07:00–08:00
May
May 1 06:00–07:00 May 2 02:00–03:00 May 3 06:00–11:00 May 4 09:00–10:00, 12:00–15:00 May 5 04:00–09:00, 11:00–12:00 May 6 08:00–11:00 May 9 07:00–09:00 May 10 05:00–09:00 May 11 12:00–13:00 May 12 02:00–03:00, 09:00–11:00 May 13 08:00–11:00 May 14 06:00–10:00 May 15 05:00–06:00, 12:00–13:00 May 16 03:00–08:00 May 17 03:00–10:00 May 19 06:00–10:00 May 20 03:00–08:00 May 21 07:00–08:00 May 23 04:00–09:00 May 26 07:00–10:00 May 27 06:00–07:00 May 28 04:00–08:00 May 29 06:00–07:00 May 30 05:00–06:00
June
Jun 10 08:00–10:00 Jun 11 07:00–08:00 Jun 12 06:00–07:00 Jun 13 05:00–07:00 Jun 14 06:00–09:00 Jun 15 10:00–12:00 Jun 16 06:00–09:00, 17:00–19:00 Jun 17 06:00–11:00 Jun 18 06:00–12:00 Jun 19 07:00–08:00 Jun 20 06:00–11:00 Jun 21 07:00–09:00, 11:00–12:00 Jun 23 06:00–08:00, 18:00–19:00 Jun 24 04:00–07:00 Jun 25 05:00–08:00 Jun 26 06:00–08:00 Jun 27 08:00–09:00 Jun 28 06:00–07:00 Jun 29 10:00–14:00 Jun 30 08:00–09:00
July
Jul 1 06:00–07:00 Jul 2 07:00–10:00 Jul 3 06:00–09:00 Jul 4 07:00–08:00 Jul 7 06:00–07:00 Jul 8 06:00–07:00 Jul 10 07:00–08:00 Jul 11 05:00–08:00 Jul 12 06:00–08:00 Jul 15 07:00–10:00 Jul 16 04:00–09:00, 11:00–12:00 Jul 17 03:00–09:00 Jul 18 11:00–12:00, 14:00–15:00 Jul 19 04:00–07:00, 09:00–10:00 Jul 20 03:00–06:00, 10:00–13:00, 17:00–18:00 Jul 21 03:00–07:00 Jul 22 03:00–05:00, 10:00–11:00 Jul 23 03:00–06:00 Jul 24 04:00–06:00, 08:00–09:00 Jul 25 13:00–15:00 Jul 26 08:00–11:00 Jul 28 03:00–05:00 Jul 29 02:00–08:00 Jul 30 03:00–07:00 Jul 31 00:00–02:00
August
Aug 7 02:00–04:00 Aug 8 02:00–07:00 Aug 10 11:00–13:00 Aug 12 02:00–03:00 Aug 13 02:00–04:00 Aug 16 04:00–07:00