Season ticket help please

[Bear Town Baggie]

I'm bordering on not renewing as attending night matches have become just too much for me. My sister in law would be willing to share a ticket and go to the night games. 
My ticket is an OAP concession, anyone know how much it costs to upgrade each game to a full adult ticket? And, can thus be done online or by phone and on the matchday?
Thanks.

[HeavyWoollenBaggie]

Copied from the OS season tickets FAQs. Presumes the same rules would apply in your situation:

I HAVE A CHILD SEASON TICKET BUT WOULD LIKE TO BRING AN ADULT TO A GAME IN THEIR PLACE, IS THIS POSSIBLE?

You can upgrade your season ticket a maximum of five times per season. To upgrade the season ticket you can either call us on 0121 227 2227 or alternatively go into the Ticket Office on the day of the game and the upgrade can be processed then. The cost will be the matchday price of the ticket minus the pro rata cost of your junior season ticket for an individual match. There will be a limit to how often this can happen.

[Squid]

Copied from the OS season tickets FAQs. Presumes the same rules would apply in your situation:

I HAVE A CHILD SEASON TICKET BUT WOULD LIKE TO BRING AN ADULT TO A GAME IN THEIR PLACE, IS THIS POSSIBLE?

You can upgrade your season ticket a maximum of five times per season. To upgrade the season ticket you can either call us on 0121 227 2227 or alternatively go into the Ticket Office on the day of the game and the upgrade can be processed then. The cost will be the matchday price of the ticket minus the pro rata cost of your junior season ticket for an individual match. There will be a limit to how often this can happen.

How interesting. I'm sure I've done that more than five times a season in the past. I wonder if that is a new rule?

[Tom Joad]

Copied from the OS season tickets FAQs.  Presumes the same rules would apply in your situation:

I HAVE A CHILD SEASON TICKET BUT WOULD LIKE TO BRING AN ADULT TO A GAME IN THEIR PLACE, IS THIS POSSIBLE?

You can upgrade your season ticket a maximum of five times per season. To upgrade the season ticket you can either call us on 0121 227 2227 or alternatively go into the Ticket Office on the day of the game and the upgrade can be processed then.  The cost will be the matchday price of the ticket minus the pro rata cost of your junior season ticket for an individual match. There will be a limit to how often this can happen.

How interesting. I'm sure I've done that more than five times a season in the past. I wonder if that is a new rule?

Possibly brought in to prevent abuse as we are going to have concession tickets as a huge percentage of our total sales? I wonder if there will be more notice taken this year upon entry? I must confess, as a group we have taken a few liberties over the years when giving away our tickets to mates, family etc.

[Bear Town Baggie]

Thanks guys.