I don't know much about these flights but maybe able to enlighten you a little more.
The flights are mainly contracted for TravelCity Direct (amongst others), who are UK based and specialise in "Fly Drives" to Florida for british tourists. this is the company that have previously contracted ATA, although those flights arn't happeining this year (hence the EAL flights).
As for the time scale of the service i'm not sure. Florida is an all-year round destination for us brits, so they may continue in the winter although muich lower capacity, perhaps one flight a week. However, saying that, the ATA flights were only summer flights, so the EAl may also be summer only. Have to wait and see!!
Hope this helps (a little!)