Most teams I see run LinkedIn first, then follow with email after 3-5 days. LinkedIn feels less intrusive and gets better open rates since there's no deliverability risk. If they engage on LinkedIn but don't respond, that's a warm signal for your email sequence.
For the workflow, push prospects from Clay into HeyReach first. Set up a simple 3-touch LinkedIn sequence (connection request, follow-up message, value-add message) over 7-10 days. Export non-responders from HeyReach and feed them back into Clay with a tag, then push to Instantly for your email sequence.
The key is giving LinkedIn enough time to work. Don't rush people into email after 48 hours. LinkedIn moves slower but the engagement quality is usually higher.
One thing to watch with HeyReach - their account health monitoring isn't as robust as some other LinkedIn tools. Keep your daily limits conservative (15-20 actions per day max) and warm up new accounts slowly. I've seen people get restricted pushing too hard too fast.
For data flow, you can use Zapier or Clay's native webhooks to automate the handoffs, but honestly most teams just do weekly manual exports until they dial in the timing. The extra automation complexity usually isn't worth it until you're pushing serious volume.
The setup works well - just don't expect immediate results. LinkedIn is a longer game but the quality conversations are usually worth the wait.