I believe MDL has signed the order of unmanned submarine already, not much is disclosed in public domain. So it's not like production line is going to get idle. 2nd there is ongoing Discussion on next SSk series along with 3 additional boats of Scorpion class. Whether that discussion converts into concrete order is yet to be seen.
Aside, I haven't seen enough push from MDL for submarine exports till now despite it being the most experienced conventional submarine builder in India. Let's hope they at least make some attempt earnestly.
I don't think the IN intends to order new Scorpenes. Had the opposite been the case , they'd have already ordered additional ones by now.
Why? I've no clue & I'm not buying the obsolescence theory being peddled. If you accept this argument it automatically follows that the current Scorpenes are themselves obsolete . All this in less than 5 yrs since the first Scorpene was inducted into service & it's more or less the same story across the world with the first of their export orders having been commissioned around a decade ago +/- 2 yrs.
In the event Naval Group has reiterated it's offer of upgraded Scorpenes plenty of times, were IN to consider additional Scorpenes. IN chose not to exercise that option. Has it something to do with leaked documents pertaining to Scorpenes on the web in Australia few yrs ago ? As of now we don't know the answer to that one though the IN & NG claims nothing confidential was revealed.
For MDL to handle exports, they ought to tie up with Naval Group preferably since we've no indigenous design of our own & since they've already collaborated before & the former can take advantage of the costs of mfg in India for export orders they bag. Frankly neither parties seem interested in it.
MDL could team up with Kockums or Thyssen Group as well but it's a bit of a long shot as both the foreign OEMs would be interested in collaboration only if GoI / MoD / IN is the client not for 3rd party deliveries , I suspect.