Most often in June, 23 days.
Highest follower count seen that year: 2,674.
April
Apr 18 07:00–15:00 Apr 20 09:00–15:00, 17:00–20:00 Apr 21 07:00–08:00, 11:00–13:00, 16:00–21:00 Apr 22 12:00–18:00 Apr 23 14:00–21:00 Apr 25 10:00–17:00 Apr 29 09:00–16:00
May
May 3 08:00–14:00 May 4 18:00–23:00 May 7 16:00–23:00 May 8 07:00–10:00 May 9 15:00–20:00 May 10 08:00–14:00 May 12 06:00–10:00 May 14 17:00–23:00 May 15 07:00–13:00 May 17 21:00–24:00 May 18 13:00–16:00, 19:00–21:00 May 21 06:00–11:00 May 22 07:00–12:00 May 23 09:00–16:00 May 24 21:00–24:00 May 25 00:00–02:00 May 28 10:00–13:00 May 29 07:00–08:00 May 31 01:00–11:00
June
Jun 1 07:00–12:00, 23:00–24:00 Jun 2 00:00–11:00 Jun 3 08:00–14:00 Jun 4 07:00–13:00 Jun 5 07:00–15:00 Jun 6 07:00–12:00, 14:00–17:00 Jun 7 07:00–14:00 Jun 9 06:00–13:00 Jun 10 08:00–14:00 Jun 12 08:00–12:00, 16:00–19:00 Jun 13 08:00–16:00 Jun 15 09:00–13:00 Jun 16 11:00–14:00, 16:00–20:00 Jun 19 12:00–16:00 Jun 21 09:00–13:00, 16:00–18:00 Jun 22 12:00–14:00, 16:00–17:00 Jun 23 10:00–17:00 Jun 24 08:00–13:00, 16:00–17:00, 19:00–22:00 Jun 25 08:00–13:00 Jun 27 08:00–17:00 Jun 28 08:00–12:00, 16:00–17:00 Jun 29 07:00–16:00 Jun 30 09:00–14:00, 16:00–19:00
July
Jul 2 08:00–12:00, 15:00–18:00 Jul 5 07:00–12:00, 14:00–17:00 Jul 6 07:00–17:00 Jul 7 08:00–16:00 Jul 8 08:00–15:00, 17:00–18:00 Jul 10 08:00–14:00 Jul 13 07:00–13:00, 15:00–17:00 Jul 14 16:00–21:00 Jul 17 10:00–17:00 Jul 18 08:00–14:00 Jul 19 11:00–19:00 Jul 20 10:00–15:00, 18:00–21:00 Jul 22 08:00–15:00 Jul 24 08:00–13:00 Jul 25 07:00–14:00 Jul 26 08:00–15:00 Jul 27 11:00–16:00, 18:00–20:00
August
Aug 5 07:00–11:00 Aug 10 05:00–09:00 Aug 11 02:00–05:00 Aug 12 07:00–09:00 Aug 13 08:00–15:00 Aug 14 09:00–13:00 Aug 15 00:00–01:00, 07:00–12:00 Aug 16 07:00–12:00 Aug 17 07:00–10:00, 12:00–16:00 Aug 18 07:00–11:00, 16:00–19:00 Aug 20 10:00–13:00, 15:00–16:00, 19:00–20:00 Aug 22 16:00–19:00 Aug 23 14:00–19:00 Aug 24 12:00–16:00, 19:00–24:00 Aug 25 11:00–12:00, 15:00–19:00 Aug 27 12:00–19:00 Aug 28 12:00–19:00 Aug 29 07:00–11:00 Aug 30 07:00–14:00 Aug 31 12:00–20:00
September
Sep 1 08:00–15:00 Sep 3 08:00–14:00 Sep 5 08:00–11:00, 14:00–16:00 Sep 6 14:00–18:00 Sep 7 07:00–11:00 Sep 12 08:00–15:00 Sep 15 01:00–05:00, 09:00–13:00, 17:00–19:00 Sep 20 01:00–04:00 Sep 21 00:00–05:00, 08:00–11:00 Sep 22 03:00–04:00 Sep 23 02:00–06:00 Sep 26 23:00–24:00 Sep 27 00:00–05:00, 08:00–10:00 Sep 28 00:00–07:00 Sep 29 00:00–04:00
October
Oct 1 08:00–11:00 Oct 2 02:00–04:00, 09:00–11:00 Oct 3 07:00–13:00 Oct 4 07:00–11:00 Oct 5 10:00–12:00, 14:00–15:00 Oct 6 09:00–11:00 Oct 8 09:00–15:00 Oct 9 11:00–15:00 Oct 10 09:00–12:00 Oct 11 09:00–14:00 Oct 12 09:00–14:00 Oct 13 09:00–13:00 Oct 14 06:00–11:00 Oct 18 23:00–24:00 Oct 19 00:00–01:00 Oct 20 14:00–21:00 Oct 25 01:00–03:00 Oct 26 02:00–03:00
November
Nov 4 06:00–10:00 Nov 6 00:00–05:00, 08:00–11:00 Nov 7 06:00–10:00 Nov 8 07:00–11:00 Nov 9 03:00–06:00 Nov 10 03:00–08:00 Nov 13 03:00–09:00 Nov 14 08:00–11:00 Nov 16 08:00–14:00 Nov 18 10:00–15:00 Nov 19 12:00–16:00 Nov 21 10:00–16:00 Nov 23 11:00–17:00
December
Dec 9 06:00–09:00 Dec 13 07:00–10:00 Dec 16 23:00–24:00 Dec 17 00:00–01:00, 09:00–11:00 Dec 19 07:00–09:00 Dec 20 09:00–11:00, 13:00–14:00 Dec 22 06:00–11:00 Dec 23 04:00–06:00 Dec 30 09:00–11:00