Same as Nick really. Do the committee know the situation and when your parents are likely to be back? I'm on our committee, and we sometimes only find out about things like this when someone has complained. Managing their plot for a season or possibly even 2 would be ok with us, as long as it would be possible for them to come back. Some of our plots are worked by families rather than one person, and it shouldn't make a difference if it's a family with young kids, or adults helping older parents. Perhaps, as well as talking to the committee, and if they are up to it, your parents could come with you to the plot? It might help if they were seen taking an interest, even if they can't do much at the moment.