SnS Compaq or Lifestyle has high RF markers.
Infa secure Neon and Kompressor also have highRF markers.
also contact Britax about your RF markers. Early batches of their seat had low RF markers. I believe new covers have higher RF markers.
Eta my 94cm DD is on the turn to FF line.
If your RFing height marker is lower than about 34-35cms then you have an old cover. All Safe N Sound convertible car seats should have the same height markers now.
Ring Britax and tell them how disappointed you are that such a young baby is at the line already, and they SHOULD offer to sent you out a replacement cover with higher height markers free of charge.
Also, is the insert out? That should give you a few extra cms.