http://https://www.globalsportssalaries.com/GSSS%202016.pdf
Page 14 gives an insight. The average weekly wage for the clubs in Brighton's sphere is say £22k to £40k per week.
20 players on £30k a week would cost the club £36m a year (including employers NI). Stars comimg in might demand...
The club would've have been silly not to. We have a massive head start being able to firm up links ahead of those living in uncertainty:
Hudd, Massive, Fulham, Reading, Leeds, Swansea, Hull.