SQL Server 2012 :: How To Drop And Create Synonym Without Client Error

A heavily-selected database will be in an inconsistent state for several hours during a batch process. For that time, a database snapshot is created and accessed instead. To allow constant client read access to the database, a database that only contains synonyms exists. Those synonyms point to the main database except during the batch process, at which time they point to the database snapshot.

To switch the synonyms, each synonym is dropped and then created pointing to the database snapshot (after its creation, of course). The drop/create occurs inside a transaction. Roughly, the SQL looks like this:

SET XACT_ABORT ON;
BEGIN TRANSACTION;
DROP SYNONYM [dbo].[some_proc];
CREATE SYNONYM [dbo].[some_proc] FOR [snapshot_db].[dbo].[some_proc];
GRANT EXECUTE, SELECT ON [dbo].[some_proc] TO public;
COMMIT TRANSACTION;

When the batch update is completed, the process is reversed with "snapshot_db" replaced with "regular_db". The SQL snippet above is dynamic SQL. What I've pasted is the dynamic SQL that is executed as a single batch.

While this switch is happening, clients are accessing the procedures through the synonyms, potentially at a high request rate. Testing reveals that clients can get the error:

Error=-2147217900, Id=0, Meaning=IDispatch error #3092,
Source=Microsoft OLE DB Provider for ODBC Drivers,
Description=[Microsoft][ODBC SQL Server Driver][SQL Server]Could not find stored procedure 'dbo.some_proc'.

This error only occurs once. If the same SPID retries its request and the transaction has not completed (for testing, a delay was added), then it blocks until the transaction completes.

Any way to prevent it besides a client-side retry?