The list that I linked to includes only those ATOs that have applied direct to EASA for approval. It does not include an unknown number who have obtained approval from individual EU member states. It will be interesting to see how many UK-based and licensed airlines are still around to accept applications from UK-licensed pilots once the dust settles. Of course, there is also the issue of how many UK pilots, although holding EASA licences, will retain the right to work in the EU.