Kindle. Apparently Brunner's first under his own name, the first-first being under a pseudonym. Space opera. There's already some of his signature moves including multitrack narration and discursive smart-arse grabs at the start of each chapter. He put in a few too many underdrawn characters including a couple of token twentieth-century everypeople. Time travel, temporal inertia and surges... parallel universes with a causality repair mechanism ... oh my. God as a disembodied woman who gifts another woman to her surviving (embodied) husband. The (xenophobic) Enemy invades! The Being ... who does stuff ... ouroboric. Conceptually cracked but you can see the promise.