Edit Stock Plan
To edit a Stock Plan, head to the Cap Table tab on the left panel. Select Plans and Equity Awards from top, then click the name of the Stock Plan you want to edit. Towards the top is the button to 'Edit Plan.'
Amend reserved shares
An amendment is done by editing an existing stock plan's reserved shares. To view previous amendments, go to Ownership > Plans & Equity Awards, click on the stock plan name to inspect it.