You'll need to wait until May 15 for the next update, @Carole673 . If it is extended, you'll need to 'attest to the facts of and/or provide supporting documentation for your extenuating circumstance'. I assume this might mean proving information such as your government's 'no international travel' rule (if this exists).
If this does happen, your host won't get to make the decision whether they keep 50% or not.