RAF IDS variants were initially designated the Tornado GR1 with later modified aircraft designated Tornado GR1A, Tornado GR1B, Tornado GR4 and Tornado GR4A. The first of 228 GR1s was delivered on 5 June 1979, and the type entered service in the early 1980s. A total of 142 aircraft were upgraded to GR4 standard from 1997 to 2003.
Source - Wikipedia
The GR1A and GR4A variants were fitted for reconnaissance.
Stationed at RAF Marham for a year, watch countless times these aircraft taking off and landing. I saw my first Tornado back in 1977 when it was put on show for the first time at the Queens Royal Review of the RAF, (I was a very young airman at the time).