My apologies, have been away on travel. You are correct, the FAA used to designate Mooneys based on the model type (i.e., M20A,B,C…).
With the new system they annouced about 18 months ago, that all changed (although many pilots still get it wrong when submitting flight plans). The new system is based on the performance characteristics of the Mooney and they break the planes down into two types:
M20P - The normally aspirated Mooneys (M20A-J, L, P, R, S)
M20T - The turbocharged Mooneys (M20K, M)
The “TLS” or “Bravo” is the name (much like Mooney Executive or Ranger) for the M20M. It is one specific model of turbocharged Mooneys. My recommendation would be to change your coding to reflect that an M20T (or M-20T) is a turbocharged Mooney (perhaps something like “Mooney(turbo)” and an M-20P is listed as “Mooney”.
Hopefully this makes sense to you, if not, please feel free to email me.
Again, keep up the great work on the site…I am proud to be a charter member and have reviewed your site in one of my trip reports on my website!
all the best,