New Delhi, Aug 30 : Apple has apparently resolved all key production issues with its iPhone 15 series, set to launch on September 12 in a global event, leading Apple analyst Ming-Chi Kuo said on Wednesday. The main production issues were with stacked CIS, panels, batteries (expanding when exposed to heat), and titanium frames. 'The stacked CIS issue has been resolved by increasing production capacity, but it still affects about 10'15 per cent of shipments of regular models,' Kuo claimed. Changing the supplier shipment ratio has resolved the panel issue while the battery and frame issues have been resolved mainly by improving production yield. 'The production challenges of titanium frames are high processing difficulty and significant design changes during development (canceling the virtual button design in 2Q23),' said Kuo, an analyst at TF International Securities, a financial services group in the Asia-Pacific region. 'The titanium frame should contribute to weight reduction,' he added. The Pro Max project was the last to kick off, so mass production schedule lags behind other models, according to him. On colours, he predicted that iPhone 15 Pro colours may be gray, white, black, and blue while the regular finishes may be black, pink, yellow, blue, and green. On Monday, Kuo predicted that Apple could see a rebound in its stock price ahead of new product announcements in September and could become the world's largest smartphone brand by 2023-2024. Apple on Tuesday revealed that its next big global product launch -- showcasing the fresh lineup of iPhone 15 series -- will happen on September 12. The tech giant is also expected to announce new Apple Watches at the event. The company said its 'Wonderlust' event will take place live from Apple Park. Some Apple iPhone 15 models are likely to support charging up to 35W that will offer faster charging speeds. Currently, the iPhone 14 Pro is limited to charging at 27W while the regular iPhone 14 offers 20W charging. For the Pro models, Apple is expected to introduce a new Action Button that will replace the Mute/Ring Switch, the A17 Bionic chip, a new titanium frame, and better cameras with a periscope lens for the iPhone 15 Pro Max, according to reports. /IANS