Why Local GMT must ignore daylight saving time

When you fill in the Local GMT field on a VICIdial phone, you enter the offset from Greenwich Mean Time and you do not adjust it for daylight saving. This is one of those settings where doing the helpful-looking thing breaks the system, so it is worth understanding why.

The short version: the dialer already handles seasonal time shifts internally. Your job is to give it a stable base GMT offset (lead) and let it do the math.

What the field is really for

Local GMT exists so the campaign can show the correct current time and the correct customer time. It is a reference point, not a live clock. If you bump it by an hour every spring and autumn, you are double-counting the shift the system is already applying.

Standard offset, all year

Pick the standard-time offset for the location and leave it alone. US Eastern stays -5 in summer and winter. London stays 0. You set it once when you build the phone entry and you never touch it again for seasonal reasons.

• Use the standard-time offset, not the summer-time one.
• Do not change it twice a year.
• Change it only if the physical phone actually moves to a new time zone.

Where the seasonal shift is handled instead

flowchart TD
  A[You enter standard GMT offset] --> B[Phone entry stores fixed value]
  B --> C[Campaign reads the offset]
  C --> D[System applies daylight saving itself]
  D --> E[Correct displayed time]
  A2[You adjust for DST manually] --> F[Offset shifted by one hour]
  F --> G[System adds its own shift]
  G --> H[Time wrong by one hour]

Because the daylight-saving math lives in the dialer and not in this field, every Agent across a Campaign gets consistent times as long as each phone holds its plain standard offset. This is also why the field sits with the other location and Dialplan settings on the phone record rather than with anything seasonal.

For how this field fits the rest of the record see the phones and aliases guide, and the phone's dialing context is covered in the phone context article.

Time-zone edge cases are exactly the sort of thing a managed host should keep correct for you. See pricing.