From those figures I think your best move may be to see if BT will downgrade you to Infinity 1 (55/10 maximum connection speed) free of charge if saving a bit would be good, of course ending up on the lower tariff.
Before asking them about that though we should look at how your connection is organised in the house. It can make several Mbps difference.
Are you connecting through an extension socket ot the master socket? If the master, using a filtered faceplate or a dangly filter?
Are there any extension sockets on the premises? It is irrelevant whether you use them or not. Just their existence matters.
Edit: Typo.
My broadband basic info/help site -
www.robertos.me.uk. Domains, site and mail hosting -
Tsohost.
Connection - AAISP Home::1 80/20. 200GB. Sync 74145/13476Kbps @ 600m. BQMs -
IPv4 &
IPv6
Edited by RobertoS (Sat 09-Dec-17 23:44:26)