Hello!
Found the culprit. Several files contained this 2 lines:
M280 P0 S160 : precautionary alarm release (reset BLTouch Probe)
and
END_PRINT
In the first one, the comment was preceded by a : instead of a ;
In the second one the comment was not preceded by ; (it was generated by the slicer – ORCA)
In the RRF/DWC V3.4.6 this was not causing any issue. But in V3.5.0_RC3 causes the error.
Hope this information may be useful for someone else.

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