The time when GTA 5 (including GTA Online, of course) is being removed from the PlayStation Plus game catalog is approaching. It and a dozen more titles will no longer be available to Extra and Premium (also known as Deluxe) subscribers on May 20th.
Often in the second half of the year, Grand Theft Auto V is replaced by RDR 2 (naturally, with Red Dead Online), but at the moment this is just speculation — there is no official information yet.
Source: gta.com.ua