M4 has been working great and I cut out a whole sheet of parts yesterday.
This morning I was greeted with the following:
Serial Messages
[MSG:ERR: sdmmc_card_init failed code 0x0x102]
[GC:G0 G54 G17 G21 G90 G94 M5 M9 T0 F0 S0]
[MSG:INFO: Channel auto report interval set to 50 ms]
[GC:G0 G54 G17 G21 G90 G94 M5 M9 T0 F0 S0]
A reboot appears to have resolved the issue