I have been watching a specialist rail forum since the accident.
Currently, and for the foreseeable future there is no rail service running north of Cordoba, with a restricted rail replacement bus service running between Puertollano/Ciudad Real and Madrid.
There are two Media Distancia trains a day running each way between Madrid and Seville via Merida/Caceres, taking 9 to 10 hours (the normal service on that route).
Trains are running between Seville and Cordoba, but Renfe/Iryo are not running RRB's from Cordoba to Puertollano and seem to have no plans to do.
Unfortunately the normal diversionary route from Cordoba to Madrid via Linares is also closed for long term engineering work.
Normal scheduled bus services are running, but are heavily subscribed with duplicate vehicles running which are reported to have no on board toilets in some cases.
Wizz Air are also running daily relief flights from Madrid to both Seville and Malaga with fares capped at no higher than 100 Euro (flights additional to those normally run by other carriers).
The signalling system on the fast line where the accident was now needs to be replaced with a more modern system (work which was ongoing at an advanced stage before the accident).
Also a lot of train sets are reported to be stranded at both Malaga and Seville.
While Cordoba has an airport it has no flights to Madrid, only to Barcelona on Vueling.
Thus that might be an option- fly to Barcelona then train to Zaragoza.
It may be possible to run some kind of rail service before then using the even older colour light trackside signalling, but those signals are very widely spaced- thus at best a very thin service can be expected once the track is repaired.
It looks to be unlikely that any significant service can be introduced in the next 3 weeks, although there is no official time scale for the works.