They have to be removed, because that's what Now TV does. It has GoT on for 2 months and then it disappears for about 6 months. This is probably decided by HBO who want to hook people in and then have them buy episodes/seasons separately.
See http://www.artesea.co.uk/nowtv/
This shows the duration of GoT (1/3/2019 - 31/05/2019)
It looks like HBO wont be extending their deal with Sky next year and will launch their own streaming service in the UK. So GoT may not return to Now TV...
