Hi Rajashekar,
Spectrum should use the system clock to keep track of schedules. So, if your maintenance schedule is "Every week on Sun from 1:30 AM for 32 hours". I would expect the device to be placed in maintenance at 1:30 AM, as scheduled. The device should not have been taken out of maintenance until the 32 hours timer has expired, and shouldn't have been impacted by the Daylight Savings change.
Just to be sure, I setup a similar scenario, where I created a maintenance schedule to happen at 1:00 PM central time today, and the maintenance would last for 12 hours, on a Spectrum 10.2.1 SpectroSERVER. I then changed the system clock of the SpectroSERVER and set it back 1 hour, to 12:00 PM after the device was placed in maintenance. The device still shows to be in Maintenance. If I fast forward the system clock 12 hours, the device is taken out of maintenance.
To get a better understanding of the events logged, I suggest opening a support case so we can review the events in question and help determine what happened to cause the alarms to be seen. We would need a copy of the $SPECROOT/Install-Tools/.history file and a copy of all the events for the device in question. Include all the events for the device and the sub-components showing when the device was placed in maintenance through the time the alarms were seen.
Thank you,
Brad