Hi:
The XX should be strong in most methods, but on bbo it might be almost anything including an attempt at self rescue with weak diamonds.
I use the XX to show something about 18+ with strong diamonds. Partner is invited to use the red card or support Ds if he sees fit.
1S is not forcing and 2S would not be forcing without the double so it should not be forcing here.
Why would you want to force? A reopening double can be much weaker than a direct double. Many freely double with 10+ here and one Italian style is to double with 8-12 or 16+(they use the next step up to show 13-15)
If the XX shows A AK AK or a somewhat better hand, why do you want to force?
Do you really want to force partner to bid higher than 2S with say 10HCP and three card spade support?
Your hand does have better positional value, however, partners' hand value likely went down in value if the XXer has an 18+ holding with mostly AK values.
A number of recent bidding problems have shown hands with @20-21 opening at the one level.
If this hand is one of them, you do not want to force partner to bid higher than 2Ss.
Regards,
Robert