[sebtron]

Yes, older phones would turn on to ring the alarm. At least the 3 I owned did, and they were all different brands.

[samtheprogram]

Symbian was on a lot of different brands, so based on a sibling comment I’d say it was a Symbian feature.

[marcinostefano]

Not really it was Siemens c35i era that have no problem with ringing alarm when switched off.