That’s weird, on our last Atlantic crossing we had to deviate for weather while on a NAT track - first time I’ve ever had to do this in about 12 years of Oceanic Ops.
We requested clearance via CPDLC and waited as long as we could, but no reply and we had to go, so we went right (south) 10nm and plus 300’. Clearance then came through saying deviate left (north). Oh well, too late. Once clear of weather, we resumed our SLOP and nothing more heard from ATC.
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