B737-500 G-THOA is currently at Luton undergoing maintenance prior to it being returned to its lessor. To replace this, G-THOE (a -300) has been temp' based at Coventry recently.
However, due to the late delivery of Thomsons' latest G-THOO (a B737-300 with Winglets!) which is to be Coventry based, there have been problems occasionally should an aircraft go tech or get delayed.
The newest B737-800 G-FDZA was rumoured to position to Coventry to help out till THOO gets delivered
FC