In a perfectly-competitive constant-cost industry, all firms will have normal profits in the long run. This fact is very clear to me as the long run supply curve is perfectly elastic and hence each good produced in the market will have an economic cost equal to the market price and hence each good sold yields a normal profit. Thus, all firms in this industry will have normal profits in the long run.
This doesn't appear to be the case in a perfectly-competitive increasing-cost industry though. In an increasing-cost industry, the long run supply curve is upward sloping and so only the marginally good will yield a zero profit upon its sale. All others goods sold will generate positive economic profits since the supply curve only equals the market price at a single point. This would mean that some firms in the industry will generate economic profits even in the long run. But every source I've read from seems to indicate that economic profits should be zero for all firms in the long run even in the case of an increasing cost industry. They seem to suggest that as firms enter the market, they push up the price of all the firms in the industry. But an upward sloping supply curve in the long run would suggest that some firms in the industry should still have average costs considerably lower than the market price and hence some of them should make economic profits in the long run. I have attached an image with a brief explanation to hopefully help make my issue more understandable.
So I guess my question is simply : do many firms in a perfectly competitive increasing-cost industry incur positive economic profits in the long run?