GF's Dad want to gift her some money

Hi.

My GF has been told her Dad who is on his own and has some reasonable wealth but is becoming elderly, wants to gift his daughter 30k to help us with a deposit. We're both in our 40s and a bit behind the property ladder game, so this would help us loads.

My GF was asking questions to me about tax etc and we have looked into.

If I understand she technically can only receive 6k a year tax free as gifts...(Assuming he doesn't give any money to anyone else).....

If he gave the money, and he regretfully passed away within 7 years, she would have to pay 40% tax on the £30k...... although his estate would help pay that I guess....

My question is, I read something about a sliding scale on the tax If the person dies at different points during the 7 years... Although have also read this only applies if the gift is over £350k... Can anyone shed any light on this.