The CBN is now printing our Journey $100's. Up until the release of the new $100, all of our 1975 Multicoloured and 1988 Birds issues were printed by the BABN, with the 1975 prefixes running from JA to JD and AJA to AJM. Then the release of the Birds 1988 $100's continued with the AJ*'s with prefix AJN and ran through AJZ, then switched to printer letter "B" in the mid 90's starting with prefix BJA and ran through BJW.
Then, just a little while ago, the debut prefix on the new $100 was BJY and after that were the EJ* prefixes, printed by CBN.
Now, the prefixes on our 1975 and 1988 $50 issues were all printed by CBN, beginning with prefix HA to HD, and then EHA to EHN, plus prefix EFA, for the 1975 issue, and the continuation of the EH*'s on the 1988 Birds $50's with prefix EHP to EHZ, and then switching to printer letter "F" early in 1993 with the release of FHA through FHZ and now FMA to FMF (as BWJM already stated!), and as of yet, the BABN have never printed our $50's.
So, with that being said, I strongly predict that the debut prefix for our new Journey $50's will indeed be AHA - although we might see one more FM* serial number prefix on our new $50's (possibly FMG) before we switch to AH*'s, just like the new $100's started with BJY and then EJ*'s
If I were you, I'd place my bet on AHA.
And that's my twoonie's worth.
Later, Jonathan