Help ID this call please!

Hi, a newbie birder here!

This recording was taken the beginning of January around 12am(midnight) in southern Hertfordshire. The same bird was calling at the same time of night the previous year too. Dec-Jan is the only time period we have heard this call. I've tried looking up nocturnal migrating bird calls but I haven't been able to ID this bird. 

It's not a great recording but the call can be heard roughly at 5s, 15s and 32s. 

Hope you guys can help! Thanks in advance. Blush

PS: I am not able to delete that m4a file form my post, apologies.

7026.Mystery bird.m4a