LoPy Invalid syntax error after DeepSleep

[HedgehogJez]

Please include the following information when submitting a bug report:

• The Pycom board you are using (e.g. WiPy 2.0, LoPy).
  LoPy L01 OEM

• The firmware version you are using. You can get it by executing the following Python code at the REPL:
  (sysname='LoPy', nodename='LoPy', release='1.18.2.r3', version='v1.8.6-849-a1641ca on 2019-02-28', machine='LoPy with ESP32', lorawan='1.0.2', pybytes='0.9.10')

• Exact steps to cause this issue
  A group of LoPy boards were set up with the machine.deepsleep() function to send a message using LoRa every 15 minutes.

• What you expected
  The devices should wake every 15 minutes, send a message and go back to deepsleep. This cycle should continue until the device is turned off.

• What happened instead
  All of the devices crashed with a "Invalid syntax error" after random amounts of time. Some after around 6 hours, while some worked for 5 days. The error pointed to different (seemingly random) lines on each of the boards, which were succesfully executed during previous cycles.

• Additional information

  1. This issue was also observed on LoPy boards using the 1.18.2.r6 release.

Any information on possible fix or workaround would really help, as I don't want to fully rely on WDT.
Kind Regards,
H.

[iwahdan88]

@HedgehogJez This is Filesystem Corruption , can you please upgrade to LittleFS FS by using the latest Development Firmware