Digest with non-existing nodes

I just received a digest which has two entries for new nodes which are missing a node type and a node id, see below. I think this was probably caused by nodes that I deleted before the digest was sent.

Here is the relevant part of the digest:

Your subscriptions on TRANSIT notify you of the following changes since the previous digest:
A new has been posted:

n/a
Read full at http://www.transit.york.ac.uk/node/
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A new has been posted:

n/a
Read full at http://www.transit.york.ac.uk/node/
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