I have a couple of questions that hopefully you all can answer.

I have an upcoming flight on March 15th.

MAD - FRA (on LH) dep. 1330 and arr. 1605
FRA - SFO (on UA) dep. 1725 and arr. 2105

This was booked through United and yesterday they told me to call them. It turns out Lufthansa cancelled the MAD - FRA segment. Lufthansa does fly from MAD to FRA two other times that day, but neither worked with my schedule. I asked and United agreed to simply remove the first segment from my ticket. I will make my own way to FRA and still take the long-haul.

1)The agent mentioned that I can apply for a refund only once the ticket has been flown. Can anyone point me to a thread that has some data points about this type of refund? The United.com/refund page just says "... refund will depend on several variables ..."

2)I have a further flight on March 15th with United from SFO to LAS, my true destination. This is a separate ticket. Is there any value in connecting or linking the tickets?

Thank you!