You can transfer using pjsip (including 302 redirect if the call has not yet been answered); see
However, this is generally a good idea only if you are sending the call to an external answering service, your headquarters, or another destination that will reliably answer and log the call.
If forwarding to a personal mobile or home phone, transfer is usually undesirable, as the call could end up in personal voicemail or an error announcement (unreachable, etc.) Also, you won’t be able to record the call, transfer it further, have a record of its duration, or even know whether it was ultimately answered.
If your provider’s contract charges per minute for both incoming and outgoing calls, you will still be charged for both legs of a redirected call. Also, with such arrangements the number of channels is just an administrative setting and can probably be increased as desired at no additional cost.
OTOH, if you get ‘unlimited’ domestic calls, you are paying a monthly charge per channel; increasing the limit will incur additional monthly charges. However, in this case the provider will almost certainly count redirected calls against your channel limit.