PAYG income instalments - sending to ATO

For payg income instalments, if these are varied and/or it is applicable to choose Option 1 or 2 (due to new income assessment year), the original has to be signed and sent to the ATO by the due date for lodgement . My question is, why in this world of technically and online portals - that this form cannot be digitally signed and uploaded via a link in the business portal to the ATO. Why do we still need to post anything to the ATO??? It just contradicts other online services and I feel we are going back into the dark ages having to sign forms manually and rely on Australia Post .Is there possibly something in the pipeline for the future to address this flaw in the system? Thank you.