Most often in April, 26 days.
Highest follower count seen that year: 16,439.
February
Feb 11 06:00–17:00, 20:00–22:00 Feb 12 03:00–14:00, 18:00–22:00 Feb 13 04:00–06:00, 08:00–10:00, 12:00–21:00, 23:00–24:00 Feb 14 00:00–01:00, 06:00–09:00, 13:00–22:00 Feb 15 03:00–06:00 Feb 16 05:00–09:00, 11:00–16:00, 19:00–21:00 Feb 17 00:00–01:00, 05:00–14:00, 18:00–22:00 Feb 18 08:00–17:00, 19:00–20:00 Feb 19 05:00–06:00, 08:00–16:00, 18:00–21:00 Feb 20 05:00–10:00, 13:00–16:00, 18:00–21:00 Feb 21 04:00–05:00, 08:00–10:00, 12:00–23:00 Feb 22 07:00–15:00, 17:00–23:00 Feb 23 05:00–13:00, 18:00–23:00 Feb 24 04:00–05:00, 08:00–17:00 Feb 25 02:00–05:00, 08:00–12:00, 19:00–21:00 Feb 26 07:00–10:00, 14:00–17:00, 22:00–23:00 Feb 27 06:00–07:00, 21:00–22:00 Feb 28 05:00–14:00, 16:00–21:00
March
Mar 1 06:00–08:00, 10:00–12:00, 14:00–16:00, 18:00–23:00 Mar 2 04:00–06:00, 08:00–09:00, 16:00–18:00 Mar 7 05:00–13:00 Mar 10 04:00–05:00, 09:00–14:00, 18:00–21:00 Mar 11 06:00–10:00, 12:00–14:00, 19:00–21:00 Mar 12 06:00–11:00, 16:00–17:00, 19:00–21:00 Mar 13 01:00–04:00, 07:00–08:00, 11:00–13:00, 19:00–21:00 Mar 14 05:00–06:00 Mar 16 08:00–13:00, 16:00–17:00, 19:00–20:00 Mar 17 06:00–12:00, 20:00–24:00 Mar 18 00:00–01:00, 06:00–07:00, 15:00–18:00 Mar 19 06:00–15:00, 18:00–22:00 Mar 20 05:00–08:00, 10:00–12:00, 15:00–17:00, 19:00–22:00 Mar 21 00:00–03:00, 15:00–18:00 Mar 22 09:00–17:00, 21:00–24:00 Mar 23 11:00–14:00, 18:00–19:00 Mar 24 09:00–23:00 Mar 25 08:00–11:00, 16:00–17:00, 19:00–24:00 Mar 26 07:00–10:00, 12:00–15:00, 17:00–24:00 Mar 27 00:00–01:00, 08:00–14:00, 19:00–20:00 Mar 28 17:00–21:00 Mar 29 07:00–09:00, 11:00–12:00 Mar 30 15:00–22:00 Mar 31 08:00–09:00, 18:00–24:00
April
Apr 1 13:00–16:00, 18:00–23:00 Apr 2 00:00–01:00, 08:00–14:00, 19:00–23:00 Apr 6 22:00–23:00 Apr 7 22:00–24:00 Apr 8 06:00–15:00, 19:00–24:00 Apr 9 07:00–08:00, 11:00–18:00, 21:00–24:00 Apr 10 08:00–12:00, 14:00–17:00, 21:00–24:00 Apr 11 00:00–02:00 Apr 12 12:00–14:00, 18:00–22:00 Apr 13 08:00–16:00, 20:00–21:00 Apr 14 13:00–19:00, 21:00–24:00 Apr 15 00:00–02:00, 09:00–12:00, 16:00–18:00, 20:00–24:00 Apr 16 07:00–12:00, 19:00–24:00 Apr 17 00:00–01:00, 08:00–10:00, 19:00–24:00 Apr 18 00:00–01:00, 09:00–11:00 Apr 20 11:00–12:00, 14:00–17:00 Apr 21 08:00–11:00, 17:00–24:00 Apr 22 02:00–04:00, 11:00–14:00, 16:00–17:00, 21:00–23:00 Apr 23 07:00–08:00, 14:00–17:00, 19:00–24:00 Apr 24 00:00–02:00, 21:00–24:00 Apr 25 00:00–02:00, 11:00–14:00, 16:00–17:00, 21:00–24:00 Apr 26 00:00–01:00 Apr 27 08:00–09:00, 12:00–17:00 Apr 28 00:00–01:00, 12:00–13:00, 22:00–23:00 Apr 29 00:00–03:00, 06:00–07:00, 14:00–18:00, 20:00–22:00 Apr 30 02:00–03:00, 15:00–18:00
May
May 1 09:00–10:00 May 7 01:00–05:00, 08:00–10:00 May 8 23:00–24:00 May 9 01:00–03:00, 07:00–11:00, 17:00–18:00, 23:00–24:00 May 10 00:00–03:00, 07:00–08:00 May 11 06:00–14:00 May 12 11:00–13:00 May 15 09:00–15:00 May 16 02:00–13:00 May 18 09:00–20:00, 22:00–24:00 May 19 06:00–12:00 May 21 08:00–13:00 May 22 06:00–17:00, 19:00–20:00 May 23 08:00–13:00
June
Jun 17 08:00–18:00 Jun 18 17:00–19:00 Jun 19 09:00–18:00 Jun 20 07:00–11:00 Jun 23 07:00–16:00 Jun 24 07:00–11:00 Jun 25 05:00–09:00, 11:00–15:00 Jun 26 06:00–12:00 Jun 27 13:00–14:00, 16:00–17:00 Jun 29 09:00–15:00 Jun 30 07:00–16:00
July
Jul 1 07:00–12:00, 20:00–21:00 Jul 2 07:00–09:00 Jul 8 08:00–17:00, 20:00–23:00 Jul 9 09:00–15:00 Jul 10 12:00–16:00, 22:00–23:00 Jul 11 07:00–11:00, 13:00–19:00 Jul 12 12:00–15:00 Jul 14 07:00–11:00 Jul 15 09:00–17:00 Jul 16 07:00–08:00 Jul 17 08:00–18:00, 21:00–23:00 Jul 18 09:00–12:00 Jul 19 20:00–23:00 Jul 20 09:00–15:00, 19:00–24:00 Jul 21 00:00–02:00, 10:00–12:00 Jul 23 09:00–18:00, 21:00–24:00 Jul 24 18:00–19:00 Jul 25 20:00–24:00 Jul 26 01:00–03:00, 11:00–15:00, 23:00–24:00 Jul 28 15:00–18:00 Jul 29 00:00–02:00, 14:00–24:00 Jul 30 01:00–04:00, 15:00–17:00, 20:00–24:00 Jul 31 00:00–01:00, 20:00–24:00
August
Aug 8 21:00–24:00 Aug 9 00:00–03:00 Aug 11 08:00–11:00 Aug 14 21:00–24:00 Aug 15 00:00–05:00, 18:00–19:00 Aug 16 04:00–07:00, 19:00–22:00 Aug 27 05:00–07:00 Aug 29 02:00–07:00, 12:00–17:00 Aug 31 05:00–09:00, 11:00–13:00, 15:00–16:00, 20:00–22:00
September
Sep 7 13:00–16:00, 20:00–23:00 Sep 8 07:00–10:00 Sep 11 06:00–09:00, 17:00–23:00 Sep 12 09:00–13:00 Sep 13 06:00–16:00 Sep 14 08:00–16:00 Sep 15 10:00–20:00 Sep 16 10:00–17:00 Sep 18 08:00–10:00 Sep 21 09:00–17:00 Sep 22 09:00–10:00 Sep 23 09:00–18:00 Sep 24 09:00–10:00 Sep 26 04:00–15:00, 19:00–22:00 Sep 27 07:00–11:00
October
Oct 10 02:00–05:00, 07:00–10:00, 12:00–13:00 Oct 11 08:00–11:00 Oct 12 08:00–10:00, 16:00–19:00 Oct 13 04:00–05:00, 14:00–16:00 Oct 14 06:00–08:00, 15:00–19:00, 21:00–24:00 Oct 15 15:00–19:00 Oct 16 08:00–11:00, 14:00–21:00 Oct 18 09:00–19:00 Oct 19 09:00–10:00, 12:00–14:00 Oct 22 07:00–14:00, 17:00–21:00 Oct 23 09:00–11:00 Oct 24 18:00–19:00 Oct 25 07:00–11:00, 13:00–16:00, 20:00–22:00 Oct 28 10:00–11:00 Oct 29 09:00–11:00, 13:00–17:00 Oct 31 08:00–11:00
November
Nov 15 11:00–12:00 Nov 17 07:00–09:00 Nov 19 07:00–11:00, 13:00–14:00, 16:00–18:00