What would solve your (and mine and many other's) issues would be more flexible alerts. Like they are in ical (remind me 3 days ahead and then 2 hours before the meeting) or "remind me to prepare report for board meeting every third friday of the month".
Such has not been implemented but many people have requested it to OmniGroup and they are, as far as I am informed, working on more flexible repeat and alert options.
Since OmniGroup uses the amount of requests for a certain feature as one parameter to decide about their working priorities it would be helpful for our common goal if you would send an email to support (
support@omnigroup.com ) and communicate your wishes. They will then add your voice to the requests.
If you have further questions, feel free to ask.