it should be model as a call option. if the deal was called ,then issuer would make a make whole payment as a liquidity provider ( as such the payment would be model as credit risk exposure of the issuer )
the call should be include an action like
<LiquidityProvider> deposit cash to <AccountName> via <Formula >
<Formula> : <Till Yield> <Bond WAL> <Curve> <Spread>
Project-Bond-Focus-Solar-ABS-2022.pdf