AIBU seeing boyfriend during lockdown

[RBFLFC]

Looking for advice please!
My partner of 7 years has shared custody of his children. The children are coming to us tomorrow until Tuesday and his ex is planning to go to her boyfriends house (they don’t live together)
My partner is high risk so I’m really concerned and don’t know what to do!

Get partner to speak to her. Either he will keep children or if they return as planned they can’t come back as she is breaching guidance as exposing herself and children to risk. The government have issued clear guidance on bf/gf set ups.