Technically there is no lock-up period on assets deposited into Single Finance's lending vaults. You can withdraw your assets anytime, except when the lending vault's utilization is too high that your withdrawal amount is greater than the available funds in the vault.
Single Finance adopts a triple-slope interest rate model to optimize the fund untilization at certain level by adjusting the slope and intercept parameters. When the utilization rate rises beyond 90%, borrowing interest increases to 100% APR (lending APY up to 150%, after fees). Although your assets cannot be withdrawn at that moment, you are also enjoying the high lending APY.
The increase in borrowing interest should attract more lenders to deposit their assets to the vault, and borrowers to repay their loans. By that time, the utilization should be lowered and you may withdraw your assets from the vault.
Why can't I see my deposited assets in the lending page nor my wallet?
It is very likely that you have staked the deposited assets back with us. If you've staked the ibTokens to our vault to earn extra SINGLE, you will need to click the expand-detail button to see the staking details. But no worries, you can still check your balance and interest accrued on the left hand side portfolio bar section.