I emailed the Council a couple of times but never heard back so I thought I'd ask here...
Could Triad Weyr's Canon ever allow for a female guard? I'm sure the answer is no, but it just seems so limiting that our timeline hasn't moved enough yet to allow females to do anything (craft or otherwise) in the Holds.
You should have a reply now - I think it was sent to the wrong heather by mistake.... oops ;)
But for anyone else who is interested, the answer is no. There are no any female guards in our version of Pern. The jobs women are allowed to do in the Holds are centered around and support the expected duties of a wife and mother. For example, herbalist, midwife, a cook or a seamstress, those roles would be open to a woman since they would be part of her duties as a wife (caring for the sick, producing children, feeding and clothing their children and their husband).