Is it possible to by a one way ferry ticket from Mljet to Dubrovnik?

[Caroline]

Is it possible to by a one way ferry ticket from Mljet to Dubrovnik?

If so, where can we buy this ferry ticket?
Is it possible to buy the ticket in advance?

We will be in Mljet on September 9.

Is it possible that the return ferry gets fulled and we cannot come back to Dubrovnik? We will be foot passenger only.

Thanks,
Caroline

[Mate]

yes you can buy one way ferry ticket from Mljet to Dubrovnik for september, but not in advance.

re: "Is it possible that the return ferry gets fulled and we cannot come back to Dubrovnik? "

it is very unlikely