LANDLORD AND TENANT!!! notice and rent arrears what rights do i have?

my landlord issued me and my partner (who is 8 months pregnant) a s.21 notice to vacate after just 6 months despite us being excellent tenants who have paid rent on time every month and kept the house in immaculate condition throughout he hasen't given us a reason for the eviction as our contract expired the day before he gave us notice so he doesn't need to supply a reason the situation I'm now in is i have 2 young sons and my baby is due ONE DAY before our eviction date i have tried to speak to the landlord but all we get is "not my problem" or "not any of my concern" my problem is that we really need to move ASAP granted, i have informed the landlord that the only way i can move is by withholding the last two months rent so i can afford another property with that money then asked him to take our deposit as part payment for the arrears and then set up a payment plan after we leave to clear the rest, but he does not seem at all interested or to that end to have a heart and be lenient and is demanding that i pay his rent immediately as it stands now i am 1 week in arrears and our eviction date is 7 weeks away what rights do i have and what rights does the landlord have also if the rent arrears matter was taken to court would we under our circumstances be ordered to pay as if we were a bad tenant who is simply refusing to pay just for the sake of it! whereas i can prove that i will not be able to move without the money form his rent and it isnt as if im refusing to pay his rent full stop ive offered to pay him once we leave do you think im being unreasonable or do you think the landlord is being unreasonable??? any help in this matter would be brilliant from anyone who may have an opinion!!!